Can't use face ID please help me

Greetings tri38,

Welcome to Apple Support Communities. The steps to help resolve this issue with Face ID can be found in the Apple Support article: If Face ID isn't working on your iPhone or iPad Pro - Apple Support

"1. Check for updates

2. Check your Face ID settings

3. Check that nothing is covering the TrueDepth camera

4. Make sure that your face isn't blocked

5. Make sure that you're facing the TrueDepth camera

6. Restart your device

7. Add an alternate appearance

8. Reset Face ID"

Should this issue persist, get in touch with Apple Support for further assistance:

Get Support

We hope this helps you.

Best regards!

See if anything here helps 

Face ID on your iPhone or iPad Pro.  *

Face ID - If an alert says has been disabled on your iPhone or iPad Pro.  *

Face ID not working.   -

Face ID not working' problems on iPhone.    -

Face ID Not Working.   -

You may need to take it in for service.

Genius Bar Reservation  -  US.    

Find a store.  -

Authorized Service Provider.  -

ASC YouTube for how to to schedule a repair at an Apple Store or Apple Authorized Service Provider – Apple Support