Sign in with your PIN
Press Win + X
Click Device Manager
Expand Cameras
Right-click Surface IR Camera
→ Click Disable
→ Wait 5 seconds
→ Click Enable
Restart the Surface.
If Surface IR Camera is missing completely, then you have to visit https://support.microsoft.com/en-us/surface
Install drivers and firmware→ Restart
Settings → Privacy & Security → Camera
Make sure:
Camera access = ON
Let apps access camera = ON
In Start Search type Services.msc and hit the Enter key. Make sure the following service is aet to Automatic and running:
Windows Biometric Service
Settings → Accounts → Sign-in options
Under Facial recognition:
If it says “Unavailable” → click Remove
Restart
Then click Set up again