Hi @Deirdre Darragh
Teams tag is mainly focused on the general issue of Microsoft Teams troubleshooting. According to your description, your question is related Microsoft Authenticator which is not in our support scope. The following suggestion is just for your reference:
Quick checks:
Make sure Airplane mode is off.
If you're using cellular, try switching to wifi and vice-versa.
If the VPN is active during the issue. If it is try deactivating the VPN to see if the issue persists.
Check if battery optimization is enabled for Authenticator. If yes, ask the user to disable battery optimization. Tap Settings and make sure Turn off battery optimization is turned on.
Make sure you run the latest version of Authenticator. Tap Settings and make sure App updates is turned on.
Make sure the device requires a PIN or biometric to unlock (lock screen). Try to re-enable faceID or fingerprint in the device settings and restart the device.
Some errors are intermittent. If you ran into a problem previously, retry your sign-in to see if the problem still occurs.
- If passwordless sign-in doesn't work, try signing in with a username and password and use a time-based one-time password (TOTP) in Authenticator for two-factor authentication as a temporary workaround.
Make sure notifications work:
Check if push notifications are turned on for the device and Authenticator. Tap Settings > Notification Settings and make sure Show notifications is turned on.
Check if push notifications are turned on for the device. On an Android device, tap Settings > Notifications > App settings and make sure Authenticator is turned on.
If you get an expired notification, make sure the device's Date & time are correct. Tap Settings > System > Date and time and make sure Automatic time and date and Automatic time zone are turned on.
- If you don't see push notifications in the list session in Authenticator, you can swipe down in the list view to check for pending authentications. You can sign in by using the pending authentication as a workaround.
More things to check:
If your device is registered, try to unregister your device in Azure AD and register it again.
Before you can access school or work resources, your organization might require you to encrypt your device.
If you're setting up multifactor authentication, try using an Incognito browser session on your laptop, then trying to scan the QR code or try using phone sign in flow instead of scan QR flow.
If you can't add your work or school account to Azure AD either through scan QR flow or the sign-in flow, try adding your Microsoft account. If you can add your Microsoft account, contact your help desk for steps to resolve the problem.
If you're using a work or school account, contact your help desk to make sure your account is not blocked any policies. Make sure your device isn't banned in a specific region. For example, Xiaomi phones were banned in USA in 2021.
You can also refer to this document for frequently asked questions about two-step verification for work or school accounts.
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