I can’t use face id

I would try these troubleshooting steps listed below.

If Face ID isn't working on your iPhone or iPad Pro - Apple Support

If that doesn't help I would schedule an appointment with Apple Support.

iPhone Repair - Official Apple Support

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.