If you're having trouble signing in to your Windows 10 device with Windows Hello, here are some things to try.
Before you begin
Make sure you set up Windows Hello on your device. For more info on how to do this, go to Learn about Windows Hello and set it up.
Check for updates
Checking for Windows updates might fix issues you're having with Windows Hello. Select Start > Settings > Update & Security > Windows Update .
Install any updates that you need. You might need to restart your device. Then try signing in using Windows Hello again.
Note: If you’ve set up multiple sign-in methods, like a password, a PIN, and Windows Hello, Windows will show those options at the sign-in screen. Select the option you want to use to sign in.
Windows Hello doesn't recognize me, or I get an error message when I try to sign in
If your face or fingerprint didn’t scan properly, or if you’re using the wrong finger to sign in, you’ll get an error message when you try to sign in through Windows Hello. If that happens, sign in with a PIN or password instead, and then set up Windows Hello again.
If you get an error message that says Couldn't recognize you. Please sign in with your PIN when you try to sign in with Windows Hello, follow the steps below to improve recognition. This error message can occur if you wear glasses and didn't set up face recognition to recognize you both with and without your glasses. This might also occur if the device has been moved and the lighting conditions are dramatically different in the new location.
To improve recognition, select Start > Settings > Accounts > Sign-in options > Windows Hello Face, and then select Improve recognition.