Quick answer: clean the top of the screen (Face ID) or the sensor and your finger (fingerprint), restart the phone, then set up your face or fingerprint again. A thick or cheap screen protector is a common cause of fingerprint failures.
Face ID (iPhone)
- Clean the notch or Dynamic Island area at the top of the screen.
- Check nothing covers it – case lip, screen protector edge or a sticker.
- Hold the phone 25–50 cm from your face; on iPhone 12 and later, try Face ID with a Mask if you wear one.
- Restart the phone.
- Reset it: Settings → Face ID & Passcode → Reset Face ID, then set up again in good light.
If you see “Face ID is not available” or “A problem was detected with the TrueDepth camera”, the sensors are damaged – usually by a drop or water. Face ID parts are paired to the phone’s board, so this needs a specialist; ask us what’s possible for your model.
Fingerprint (Samsung, Pixel and others)
- Clean and dry your finger and the sensor. Wet, dry or cold fingers read badly.
- Screen protector: under-screen sensors need a compatible protector. Turn on Touch sensitivity / Screen protector mode in display settings, or try without it.
- Re-register your fingerprint: delete it and add it again, and add the same finger twice for better accuracy.
- Update and restart the phone.
After a screen replacement, under-screen fingerprint sensors may need recalibrating. When we replace a screen, we test fingerprint and Face ID with you before you leave.
Still not working?
If the sensor never responds, or stopped after a drop or a crack across it, it may be damaged. Bring it in – we’ll check whether it’s the screen, the sensor or a setting.
Walk in – no appointment
Home visit in London
Post it to us
Fix it yourself
Fix it yourself
Fix it yourself