I’m sorry to hear you are having trouble accessing your account. It sounds like your Facebook account has disconnected from the Duo Mobile app. This commonly occurs if you get a new phone, delete the Duo Mobile app, or temporarily disable your Facebook account.
This is a protection that you’ve applied to your Facebook account. When you set this up, Facebook provided a secret key that Duo Mobile uses to generate passcodes. That key is securely stored on the device you originally installed the app on and is not transmitted to Duo’s cloud service for your privacy and security.
Did you save any of the recovery codes generated by Facebook when you set up 2FA? Do you have any alternate 2FA methods available, such as having Facebook text you a code to the same phone number you used for your account previously? If so, you can try those methods.
If you are unable to recover your account in those ways, you will need to reach out to Facebook support for assistance.
To avoid being locked out like this in the future, please note that you can back up third-party accounts. Instructions for doing so on iOS and Android are available in our end-user guide: iOS: https://guide.duo.com/duo-restore#enable-backup-3pr-ios / Android:https://guide.duo.com/duo-restore#enable-backup-android. Reference the appropriate third-party account sections.
