The fingerprint scanner on my surface duo 2 has stopped working abruptly. How to get it started again - I switched it over to SAFE MODE and it still didn't work

Hello mark,

Welcome to Microsoft Community.

I'm sure you've tried completely shutting down the device and then restarting the Surface Duo 2, but that doesn't make the fingerprint recognition function work again.

In this case, I recommend that you back up all the data in the Surface Duo and try to restore the Surface Duo 2 to factory Settings:

Reset Surface Duo to factory settings - Microsoft Support ****

If the fingerprint recognition function still doesn't work when you reset the Surface Duo after restoring the factory Settings, it's time to send your Surface Duo to the Surface Support team for inspection or repair.

I can direct you to Surface Live support, who can help you create a service order:

1. Use your personal Microsoft account (not your organization account) to access the following links:

Contact - Microsoft Support

2. Type The fingerprint scanner on my surface duo 2 has stopped working, press Enter, and click "Contact Support" at the bottom:

3. Select Technical Support and select the device model you are currently using in Produce family, then click Confirm:

4. You will see contact options for Chat support and Phone support, please contact them during business hours:

I wish you all the best. 

Best Regards,

Mitchell | Microsoft Community Support Specialist