Use the Microsoft Authenticator app to scan the QR code or manually input the key. The app will give you a code to enter. Go back into Facebook and input the code.

To use Microsoft Authenticator with a non-Microsoft site or app, you'll need to have the QR code handy from the site or app in question so that you can scan it within the Authenticator app.

Instantly, the Configure mobile app screen will appear on your PC screen, displaying a QR code. You will need to scan this code with the authenticator app. Now, open the Microsoft Authenticator ...