Face ID reset failure on iPhone

Hello,

Apple has several documents helping you with Face ID.

This Support article is specific to seeing an ‘issue’ or 'disabled' Face ID alert, and explains what to do when you see that notice or an issue with the TrueDepth camera. --> If an alert says Face ID has an issue on your iPhone or iPad Pro - Apple Support

Unless a software update solves the problem you may need to have Apple take a look at your device. Use this link to set up an appointment —> Genius Bar Reservation and Apple Support Options - Apple and this one to get a repair estimate —> iPhone Repair and Service - Apple Support

If you don't see a 'disabled' message but do have general issues with Face ID not working properly, explore the list in this article of things to try: If Face ID isn't working on your iPhone or iPad Pro - Apple Support

If the first 8 don't solve the issue then use #9, contact Apple. To do that, click on —> https://getsupport.apple.com/ , select iPhone, then scroll down to the contact methods.

One person reported that simply cleaning the lens got Face ID working again —> Face ID stopped working and will not reset - Apple Community