How do I Repire my damage Face ID
How do I replace my damaged Face ID?
iPhone XS Max
Question marked as
Have a look at these two articles -
If an alert says Face ID has been disabled on your iPhone or iPad Pro
If an alert says Face ID has been disabled on your iPhone or iPad Pro - Apple Support
If Face ID isn't working on your iPhone.
If Face ID isn't working on your iPhone or iPad Pro - Apple Support (AZ)