Hi glynis104,
Thanks for contacting Apple Support Communities!
We understand that you're unable to use Face ID on your iPhone.
We see that you've also reviewed If Face ID isn't working on your iPhone or iPad Pro. If you've already completed the steps outlined in this article, you may need service for your iPhone.
Get serviceIf you still can't enroll your face, contact Apple Support.You should always have your device repaired by Apple or an authorized service provider. Improper repair, modification, or use of non-genuine Apple components in the laser systems may prevent the safety mechanisms from functioning properly, and could cause hazardous exposure and injury to eyes or skin.
We hope this helps.
Take care!