Thank you for posting your inquiry here in Microsoft Community, sanjeevgarg1.
We are sorry to hear about the Windows hello and touch screen issue. Here are the methods that we suggest:
- Run Surface Diagnostic Toolkit.
- Run the System File Checker.
- For the Face recognition, try to remove the current face recognition that you have set up and add a new face log in.
- For the touch screen, refresh the drivers. Open Device Manager then go to Human Interface Devices > look for "Uninstall HID-Compliant Touch Screen" > Right-click on HID-Compliant Touch Screen > Uninstall (if you're seeing two HID Compliant Touch Screen, Uninstall the two drivers). > Restart the device.
Let us know how this goes by replying on this thread so we can further assist.