Can't Authenticate with Duo - Enrolled Using Fingerprint or Face ID

Environment

Duo Security two-factor authentication system.

Issue

Your Duo account was set up with a Platform Authenticator as your authentication method. A Platform Authenticator uses security features built into a device, such as:

  • Face ID or Touch ID on an iPhone or iPad
  • Touch ID on a Mac
  • Windows Hello on a Windows computer
  • Fingerprint or facial recognition on an Android device

To help prevent you from being locked out of your CSUN account, the phone number associated with your account has been added to Duo as an additional authentication method.

Resolution

If you are signing in from a device where your Platform Authenticator is not available, you can use your phone number instead.

  1. Sign in to the CSUN service as you normally would.
  2. When the Duo authentication screen appears, Duo may automatically try to use your Platform Authenticator, such as Face ID, Touch ID, Windows Hello, or your device's fingerprint reader.
  3. If a Face ID, Touch ID, Windows Hello, passkey, fingerprint, or similar prompt appears and you cannot complete it, cancel or close that prompt to return to the Duo screen.
  4. On the Duo screen, select Other options.
  5. Select one of the phone authentication options associated with your phone number:
    • Text message passcode — Duo will send a one-time passcode to your phone by text message. Enter the passcode on the Duo screen and select Verify.
    • Phone call — Duo will call your phone. Answer the call and follow the instructions to complete authentication.
Duo

You do not have to use the Platform Authenticator if it is unavailable. Select Other options and use your registered phone number instead.

Platform Authenticators Are Device-Specific. A Platform Authenticator uses authentication technology built into the device on which it was configured.

For additional support, contact the IT Help Center.