Facial Recognition Works for One Person but Not Another: Causes and Solutions

One family member walks towards the digital lock and is recognised quickly.

Another person stands in front of the same lock but is not recognised consistently.

Depending on the lock model, the device may continue scanning briefly, report an unsuccessful recognition attempt or return to standby.

Does this mean the facial-recognition sensor is faulty?

Not necessarily.

Facial recognition can vary between users depending on:

• The position used during registration
• The distance from the installed sensor
• The angle of the face
• The user’s standing position relative to the camera
• Hair or accessories covering facial features
• Lighting at the entrance
• Battery condition
• Changes to the person’s appearance

If only one person is affected, try registering that user again from a natural and repeatable standing position.

If every registered user suddenly becomes unrecognisable, the camera area, battery or lock hardware may require further assessment.

Jump to a Section

• How facial recognition works
• Why recognition differs between users
• Common causes of recognition failure
• How to register a face properly
• Sudden problem vs problem from the beginning
• Facial recognition for children
• Recognition at night
• Troubleshooting steps
• When it may be a hardware issue
• Why backup access is important
• Frequently asked questions

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How Does Digital Lock Facial Recognition Work?

The exact recognition technology and scanning process vary between digital lock models.

During registration, the lock captures identifying facial information while the user stands in front of the installed sensor.

When the person approaches again, the system captures a new scan and compares it with the stored facial record.

For recognition to succeed, the lock needs a sufficiently clear and comparable view of the user’s face.

Recognition may become less consistent when:

• The user stands in a substantially different position from registration
• The face is partially covered
• The person looks away from the camera
• The lighting differs significantly
• The user stands outside the effective scanning area
• The person’s appearance has changed

What May Happen When the User Is Not Recognised?

The response depends on the lock model.

The lock may:

• Continue scanning for a short period
• Display or announce an unsuccessful recognition attempt
• Return to standby or sleep mode
• Require the user to wake the sensor and try again

A failed scan does not automatically mean that the stored facial record has disappeared or that the sensor has failed.

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Why Does Facial Recognition Work for One Person but Not Another?

Facial-recognition performance may differ between users.

Two family members may differ in:

• Their natural approach to the door
• Their standing position relative to the installed sensor
• The angle at which they face the camera
• The distance they maintain from the lock
• Their hairstyle or facial hair
• The accessories they wear
• The conditions under which they were registered
• How much their appearance has changed

One user may naturally return to approximately the same distance and angle used during registration.

Another may approach from the side, stand farther away or look down towards the handle rather than towards the sensor.

With regular use, many users become more familiar with the position that gives the lock a clear view.

However, the registration position should still be natural and comfortable. A user should not need to bend, stretch or stand awkwardly every time they unlock the door.

One User May Have Been Registered from a Better Position

The difference may begin during initial registration.

One person may have:

• Stood directly in front of the installed sensor
• Used a comfortable distance
• Kept the face clearly visible
• Registered under suitable lighting
• Looked naturally towards the camera

Another person may have registered while standing too close, too far away or at an unusual angle.

The second user’s normal daily approach may then differ significantly from the position stored during registration.

The User Approaches the Lock Differently

Recognition may also be affected by the way a person approaches the door.

For example, the user may:

• Stand too far to one side
• Move past the sensor too quickly
• Look down towards the handle
• Stand extremely close to the camera
• Remain outside the intended scanning area

Stand naturally in front of the installed sensor and give the lock a clear view before attempting to open the door.

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Common Reasons a Digital Lock Does Not Recognise a Face

1. Hair Is Covering Part of the Face

Long hair, a fringe or loose hair across the face may cover visible features used during recognition.

This may be more noticeable when the hairstyle during registration was different.

Before scanning:

• Move hair away from the eyes
• Keep the central facial area visible
• Avoid allowing hair to cover most of one side of the face

The user does not necessarily need to maintain the same hairstyle permanently, but extensive face coverage may reduce recognition consistency.

2. The User Is Wearing a Mask

A mask covers a significant portion of the lower face.

Depending on the recognition system, this may prevent the lock from capturing enough comparable facial information.

Where safe and appropriate, remove the mask before scanning.

3. Sunglasses Are Covering the Eyes

Dark sunglasses can cover the eye area and change the visible appearance captured by the sensor.

Clear spectacles may be less disruptive, although performance still varies by model and registration quality.

If recognition is poor, remove the sunglasses and try again.

4. Facial Hair Has Changed Significantly

A large or substantially changed beard can alter the visible shape of the lower face.

Recognition may become less consistent when the user:

• Grows a substantial beard after registration
• Removes a beard that was present during registration
• Changes the beard shape significantly

If recognition becomes unreliable after a major facial-hair change, register the user again.

5. The User Is Standing Too Far Away

The lock may not capture enough facial detail when the user is outside its effective scanning area.

Possible signs include:

• The lock does not begin scanning
• The user is recognised only after stepping closer
• The recognition attempt ends before a clear scan is captured

Approach the lock naturally and use the distance recommended for the particular model.

6. The User Is Standing Too Close

Standing too close can also affect recognition.

The camera may not capture enough of the full face when the user is positioned directly against the lock.

Take a small step back and face the sensor naturally.

7. The Face Is at a Different Angle

The user may have registered while looking directly towards the sensor but later attempts to unlock while:

• Looking down
• Turning towards the door
• Approaching from the side
• Leaning away from the camera

A small difference may not matter, but a significantly different angle can reduce recognition consistency.

8. The User’s Position Relative to the Sensor Has Changed

The camera is installed at a fixed position.

The user’s normal face position relative to that camera may change over time.

This may happen when:

• A child grows taller
• The user originally registered while bending or standing unusually
• The face was registered before the lock reached its final installed position
• The user now stands at a different distance
• The user’s natural posture has changed

The issue is not height alone. It is whether the face remains within a suitable position and angle relative to the installed sensor.

Register the user while they are standing naturally in front of the completed installation.

9. Lighting Conditions Are Different

Lighting may affect the clarity of the facial scan.

Recognition may be less consistent when:

• Bright light is directly behind the user
• The entrance is much darker than during registration
• The user registered at night but mainly unlocks during the day
• Strong sunlight or reflections reach the camera
• The face is heavily shadowed

Many facial-recognition locks are designed to operate across normal household lighting conditions, but performance can still vary by model and installation environment.

10. The Camera or Sensor Area Is Dirty

Dust, fingerprints, oil, condensation or residue can reduce image clarity.

Clean the camera or sensor area gently using a soft, dry microfibre cloth.

Avoid:

• Scratching the lens
• Using abrasive cleaners
• Spraying liquid directly onto the lock
• Applying strong chemicals

11. The Battery Is Low

A low or nearly flat battery may affect the camera, processor or recognition sequence.

The lock may still wake or begin scanning while behaving inconsistently.

Check and restore the battery power before deleting user records or concluding that the sensor is faulty.

12. The User’s Face Has Changed Significantly

A registered facial record may become less suitable after a major appearance change.

Examples may include:

• Significant facial surgery
• Major swelling
• A substantial change in facial hair
• A child’s face changing as they grow
• Hair repeatedly covering much more of the face

If the user’s current appearance differs substantially from the registered appearance, delete the old record and register the face again.

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How to Register a Face Properly on a Digital Lock

Good registration is one of the most important factors in reliable facial recognition.

Step 1: Register at the Installed Lock

Where possible, register after the digital lock has been installed in its final position.

This allows the user to register from approximately the same place they will use each day.

Step 2: Stand Naturally

Stand in front of the lock without bending excessively or stretching towards the camera.

The position should be comfortable enough to repeat during normal daily use.

Step 3: Use a Comfortable Distance

Do not stand extremely close or far away.

Move into the normal detection area and allow the lock to capture a clear view of the face.

Step 4: Keep the Main Facial Features Visible

During registration:

• Move hair away from the face
• Remove dark sunglasses
• Remove a mask where appropriate
• Look naturally towards the sensor
• Avoid covering the eyes, nose and mouth

Step 5: Follow the Lock’s Prompts

Depending on the model, the lock may ask the user to remain still, move closer or adjust their face position.

Follow the instructions displayed or announced by the lock.

Step 6: Use a Repeatable Position

The user does not need to memorise an exact measurement.

However, the general registration position should be natural enough to repeat when approaching the door normally.

With repeated daily use, returning to a suitable position may become habitual.

Step 7: Test Several Times

After registration, test recognition more than once.

Try:

• The user’s normal approach to the door
• A slightly different natural angle
• Daytime lighting
• Evening lighting

If the user is repeatedly rejected from the beginning, register the face again rather than assuming that the recognition will improve without adjustment.

Can the User Be Registered Again?

If recognition repeatedly fails, delete the existing facial record and register the person again.

This may help when:

• The original registration angle was poor
• The user was too close or too far away
• The lighting was unsuitable
• The person’s appearance has changed
• The user’s natural position relative to the sensor has changed

Registration capacity and whether duplicate records are supported depend on the lock model.

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Did Recognition Fail from the Beginning or Start Failing Suddenly?

The timing of the problem is an important diagnostic clue.

If Recognition Has Been Poor from the Beginning

Check whether:

• Only one user is affected
• The user registered from an uncomfortable position
• The face was partially covered
• The user stood too far away
• The face angle was unsuitable
• The lighting during registration was poor

If other users are recognised normally, delete and register the affected person again from a natural and repeatable position.

If Recognition Worked Before but Suddenly Became Poor

Check for recent changes such as:

• A dirty camera or sensor area
• Low battery power
• A new hairstyle covering the face
• A mask or sunglasses
• A large change in facial hair
• Changes to entrance lighting
• A significant change to the user’s face

Clean the sensor area and restore sufficient battery power first.

If the problem continues, register the user again.

If Every User Suddenly Becomes Unrecognisable

A wider issue becomes more likely when:

• No registered users are recognised
• The camera does not activate
• The scanning function behaves abnormally
• The problem began suddenly
• Cleaning and battery checks do not help

Contact the lock supplier for further assessment.

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Facial Recognition for Children

Children may be recognised successfully, but their registration may need to be updated as they grow.

Possible reasons include:

• The child’s standing position relative to the sensor changing
• The natural face angle changing
• The face changing as the child develops
• Hair covering more of the face
• The original registration being completed from an awkward position

If recognition was previously reliable but becomes less consistent after a period of growth, register the child again from their current natural standing position.

Do Not Make the Child Stand Awkwardly

The child should not need to stand on tiptoe, bend excessively or stretch towards the sensor every day.

Where facial recognition remains impractical, provide another authorised access method such as:

• Fingerprint
• Palm vein recognition
• PIN
• Access card

The suitable options depend on the lock model and the child’s ability to use them safely.

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Does Facial Recognition Work Differently at Night?

Facial recognition may be less consistent under certain low-light conditions, although many locks continue operating normally at night.

Performance may depend on:

• The lock’s camera and illumination system
• The amount of corridor lighting
• Strong light behind the user
• Reflections near the camera
• The user’s distance and face angle

A user registered only in very dark conditions may experience a different result during bright daytime use, and the reverse may also occur.

Improving Recognition at Night

• Face the sensor naturally
• Stand within the normal detection area
• Keep the camera area clean
• Avoid standing with a strong light directly behind the head
• Give the lock a moment to begin scanning

If recognition repeatedly fails at night but works during the day, record a video showing the entrance lighting and user position for further assessment.

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How to Troubleshoot Facial Recognition That Works for Only Some Users

Step 1: Check Whether Other Users Are Recognised

Test at least one other registered person.

If other users work normally, the issue is more likely related to the affected person’s record, position or appearance.

Step 2: Keep the Face Visible

Remove or adjust:

• Hair covering the eyes or face
• A mask
• Dark sunglasses
• A hat positioned low over the face

Step 3: Adjust the Standing Position

Move slightly closer or farther away and stand naturally in front of the sensor.

Avoid leaning, looking down or turning away while scanning.

Step 4: Clean the Camera or Sensor Area

Use a soft, dry microfibre cloth.

Do not spray cleaning liquid directly onto the lock.

Step 5: Check the Battery

Recharge or replace the battery if it is low or nearly flat.

Test recognition again after sufficient power has been restored.

Step 6: Consider Recent Appearance Changes

Check whether the user has:

• Changed hairstyle significantly
• Grown or removed a large beard
• Started wearing sunglasses regularly
• Had facial surgery
• Changed substantially since registration

Step 7: Delete and Register the User Again

Register the person from a comfortable and repeatable standing position.

Keep the face visible and follow the instructions provided by the lock.

Step 8: Test Several Attempts

Test recognition:

• Immediately after registration
• After the lock returns to standby
• During normal daytime conditions
• During normal evening conditions

Step 9: Use a Backup Access Method

Do not depend on facial recognition as the affected person’s only available access method.

Register another supported option such as a fingerprint, palm, PIN or card.

Step 10: Contact the Lock Supplier

Arrange further assessment when:

• No users are recognised
• The camera does not activate
• The problem began suddenly for everyone
• The affected user cannot complete registration successfully
• Cleaning, charging and re-registration do not help

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When Might the Facial-Recognition Hardware Be Faulty?

A sensor or hardware issue becomes more likely when:

• No registered users are recognised
• The camera or sensor does not activate
• The lock repeatedly fails to begin scanning
• The recognition function previously worked for everyone
• The battery has sufficient power
• The sensor area is clean
• Users cannot complete a new facial registration
• The problem continues after an approved restart

What Can a Technician Check?

A technician may:

• Test recognition with several users
• Check whether the camera activates correctly
• Inspect the camera or sensor area
• Confirm the battery condition
• Test facial registration
• Review the user’s standing position and distance
• Check the internal connection or recognition module
• Determine whether a component requires replacement

What If the Lock Could Not Recognise Anyone from the Beginning?

If the facial-recognition function cannot register or recognise users from the start, the installation position, setup method and hardware should be checked.

Send a video showing:

• The user approaching the lock
• The camera or sensor response
• The standing distance
• The face position and angle
• Any message shown or announced by the lock

This helps determine whether the cause is registration, user positioning or a possible hardware issue.

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Why Every User Should Have a Backup Access Method

No biometric access method should be the only way a regular user can enter the home.

Facial recognition may be affected temporarily by:

• A mask
• Sunglasses
• Hair covering the face
• Lighting
• A significant appearance change
• Low battery power

Depending on the digital lock, backup methods may include:

• Fingerprint recognition
• Palm vein recognition
• PIN access
• Access card
• App access
• A mechanical emergency key

Regular users should know how to use at least one alternative method.

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How to Reduce Future Facial-Recognition Problems

• Register each user at the installed lock
• Use a natural and repeatable standing position
• Keep the camera or sensor area clean
• Keep the face visible during registration
• Avoid registering with dark sunglasses or a mask
• Test recognition in normal daytime and evening conditions
• Register children again after significant growth
• Register users again after major facial changes
• Keep the battery sufficiently charged
• Provide each user with an alternative access method

Facial recognition may become easier as users become familiar with the effective scanning area.

However, repeated failure should not simply be dismissed as user error. Register the person again from a natural position and arrange further assessment if the problem continues.

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Frequently Asked Questions

Why does the digital lock recognise me but not another family member?

The other user may have registered from a different distance, position or angle. Hair, masks, sunglasses, facial hair, lighting and changes in appearance may also affect recognition.

Does this mean the facial-recognition sensor is faulty?

Not necessarily. If other users are still recognised normally, register the affected person again from a natural and repeatable position before concluding that the sensor has failed.

Why does long hair affect facial recognition?

Hair may cover the eyes, face shape or other visible features used during recognition. Moving the hair away from the face may improve the scan.

Can I use facial recognition while wearing a mask?

Performance depends on the lock model, but a mask may cover too much of the face for consistent recognition.

Do sunglasses affect facial recognition?

Dark sunglasses can cover the eye area and may reduce recognition consistency. Remove them if the lock repeatedly rejects the user.

Can a large beard affect facial recognition?

A significant change in facial hair may alter the user’s visible appearance. Register the person again if recognition becomes unreliable.

How far should I stand from the lock?

Use the normal detection distance stated for the lock. Stand naturally where the sensor can capture a clear view of the face without being extremely close or far away.

Why does the lock work when I move closer?

The user may have been standing outside the effective scanning area. Register and use the lock from a comfortable position within that area.

Why does it recognise me only at one angle?

The registered record may have been captured from a narrow or unusual position. Delete it and register again while facing the installed sensor naturally.

Can lighting affect facial recognition?

Yes. Strong backlighting, heavy shadows, reflections or very different lighting from registration may reduce recognition consistency.

Does facial recognition work at night?

Many locks can operate at night, but performance varies by model, entrance lighting and user position. Recognition may be less consistent under some low-light conditions.

Can low battery power affect facial recognition?

Yes. A low or nearly flat battery may affect the camera, processing or recognition sequence.

Should I register the face again?

Yes, when recognition repeatedly fails, the user’s appearance has changed or the original registration position was unsuitable.

Why did my child’s facial recognition stop working?

The child’s face or standing position relative to the sensor may have changed as they grew. Register the child again from their current natural position.

What should I do if no users are recognised?

Clean the camera area, check the battery and test several registered users. Contact the lock supplier if recognition previously worked but now fails for everyone.

What should I do if facial recognition never worked properly from installation?

Check the registration position, distance, face angle and lighting. If the lock cannot register or recognise users after correct setup, arrange an assessment for a possible installation or hardware issue.

Should facial recognition be my only access method?

No. Each regular user should also have another authorised method such as fingerprint, palm, PIN or card access.

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Need Help with Facial Recognition on Your Digital Lock?

If only one user is affected, begin by checking their standing position, face angle, hair, accessories and registration.

Clean the sensor area, restore sufficient battery power and register the affected person again from a natural, comfortable and repeatable position.

If no registered users are recognised or the camera no longer activates, the lock may require further assessment.

Facial-recognition performance varies according to the lock model, registration quality, user position relative to the installed sensor, distance, face angle, lighting, face coverage, battery condition and changes in appearance. Recognition may differ between users even when the same lock is used.