Hello, thank you for reaching out to Microsoft Q&A.
Try reinstalling the camera drivers once and see if you can enable Windows Hello Facial Recognition again:
To do that,
- Open the Device Manager.
- Expand the arrow next to Cameras.
- Right-click your default camera driver, select Uninstall device, select the 'Attempt to remove the driver software for this device' checkbox, and click Uninstall.
- Once uninstalled, restart your computer and set up Windows Hello Facial recognition again.
If that didn't work,
Check for Windows updates and download and install Optional updates as well.
(You can find the optional updates in Advanced options on the Windows updates page.)
If you are still having issues,
Type msinfo in the search bar on the taskbar and click Enter.
Post a screenshot of the resulting dialog box.