My phone Face ID not working

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If you still need help, reset Face ID, then set it up again. Go to Settings, tap Face ID & Passcode, then tap Reset Face ID. Next tap Set up Face ID to set it up again.

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

If your iPhone has a history of Camera replacement / Repair / Service from an un-authorised service provider then it is possible that Apple may refuse to service your iPhone if it has been previously serviced by an unauthorized service center.

Get a Genius Bar Reservation and Apple Support Options - Apple

Contact Genius Bar.

Manage Reservations - My Reservations - Apple

My Face ID Not working