How to Reset Face ID on iPhone & iPad
If you discover that Face ID is not reliably unlocking iPhone or iPad, you may want to try resetting Face ID and then setting it up again. Additionally, you can disable Face ID completely by resetting Face ID on a device and then not setting it up again. Resetting Face ID is pretty simple and it causes iPhone 11, 11 Pro, XS, XR, X, & iPad Pro to ditch the facial recognition data on the device, which you can then configure again if desired. Some users may find they need to do this if they dramatically change their personal appearance, but it can also be a helpful troubleshooting step if you’re trying to get Face ID to work better.