My face ID has stopped working and will not allow me to reset

If you still need help, reset Face ID, then set it up again. Go to Settings > Face ID & Passcode and tap Reset Face ID. Then tap Set up Face ID to set it up again. If you can't enroll your face, take your device to an Apple Retail Store or Apple Authorized Service Provider or contact Apple Support.

If Face ID isn't working on your iPhone or iPad Pro - Apple Support