Follow these steps. After each step, see if you still need help.
Check for updates
Make sure that your iPhone X or later is updated to the latest version of iOS.
Check your Face ID settings
To check your Face ID settings, go to Settings > Face ID & Passcode. Make sure that Face ID is set up and that the features you’re trying to use Face ID with are turned on.
Check that nothing is covering the TrueDepth camera
Make sure that the TrueDepth camera on your iPhone isn't covered with a phone case or a screen protector. Also, check to see if there’s residue or dirt covering the TrueDepth camera.
Make sure that nothing is covering your face
Make sure that your eyes, nose, and mouth are fully visible to the TrueDepth camera.
Face ID works with many sunglasses. If you're wearing sunglasses designed to block certain types of light, then your sunglasses might be blocking the infrared light used by the TrueDepth camera. Try using Face ID without your sunglasses.
Make sure that you're facing the TrueDepth camera
Face ID only works when your iPhone is in portrait orientation and you’re facing the TrueDepth camera. The TrueDepth camera has a similar range of view as when you take a selfie or make a FaceTime call. Whether your iPhone is lying on a surface or you're holding it in a natural position, make sure that your iPhone is an arm’s length or closer (10-20 inches) from your face.
Add an alternate appearance
For most users, Face ID will continuously learn as they change. If you have an appearance that can look vastly different, you can set up an alternate appearance so Face ID still recognizes you.
To set up an alternate appearance:
- Go to Settings > Face ID & Passcode. If asked, enter your passcode.
- Tap Set Up an Alternate Apperance.
- Look straight into your iPhone and place your face inside the frame.
- Gently move your head to complete the circle. If you're unable to move your head, tap Accessibility Options.
- When you finish the first Face ID scan, tap Continue.
- Gently move your head to complete the circle for a second time.
- When Face ID setup is complete, tap Done.
Reset Face ID
If you need to enter your passcode
You might need to enter your passcode or Apple ID instead of using Face ID in these situations:
- The device has just been turned on or restarted.
- The device hasn’t been unlocked for more than 48 hours.
- The passcode hasn’t been used to unlock the device in the last six and a half days and Face ID hasn't unlocked the device in the last 4 hours.
- The device has received a remote lock command.
- After five unsuccessful attempts to match a face.
- After initiating power off/Emergency SOS by pressing and holding either volume button and the side button simultaneously for 2 seconds.