If you use an OTP to sign into your Windows 10 workstation and you are not logged in afterwards, you might have a time sync issue. 

The time on your phone and workstation need to be within 1 minute of each other. If they are out of sync by ~ 1 minute or more, you will not be able to sign into your workstation with an OTP.

We recommend setting both your phone and workstation to automatically update the date and time, based on your timezone.