how can i fix my face id on my own?

See if anything here helps 

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

Face ID not working.   -

Face ID not working' problems on iPhone.    -

Fix iPhone X Face ID Not Working.    -

Face ID Not Working.   -

Face ID failure is a hardware issue. ⚠️

Get expert service and support at the Genius Bar.

Click ▶︎ Start a Service Request. ⚛️

Need more help?

• Call Apple Support at 1-800-APLCARE. 📞
• International Support. 🌐
• Contact Apple Support. 📝
• Chat using Messages. 💬

Click ▶︎ Check Repair Status.

Hey there,

See ☞ If an alert says Face ID has been disabled on your iPhone or iPad Pro - Apple Support

These don’t work. They’re also from 3 years ago.