I can't access my Teams institutional email

This is a circular MFA sign-in problem. For a work or school account, the Microsoft Authenticator and Teams sign-in methods are managed by the institution’s IT administrator.

Try these steps in order:

1. On the sign-in screen, look for Sign in another way or Try another verification method.
   • If another method is already registered, use it.
   • Possible alternatives include SMS, phone call, office phone, or email, depending on what was previously configured.
2. If no other method appears, or only Authenticator is available, this usually means no backup verification method is registered for the account.
3. Contact the school or university IT help desk and ask them to reset MFA settings or allow MFA re-registration for the institutional account.
   • A clear description to provide is: stuck in a login loop between Microsoft Teams and Microsoft Authenticator after changing devices.
4. After the MFA settings are cleared or reset by the administrator, sign in again.
   • The account should prompt for MFA setup from the beginning.
   • At that point, Microsoft Authenticator can be registered again on the new device.

If repeated sign-in attempts were made, Microsoft Entra multifactor authentication can temporarily block additional attempts. In that case:

• stop making repeated attempts,
• wait until sign-in is allowed again, or
• use a different verification method if one is available.

If the old phone was lost or is unavailable, the documented path is to use another registered method or have the organization’s Help desk clear the MFA settings.

References:

• Common problems with two-step verification for a work or school account
• Use a screen reader to set up and troubleshoot multifactor authentication
• need help logging back in microsoft teams and authenticator - Microsoft Q&A
• I would like to connect to my account but the app requires me to enter a code which I can only access if I am connected - Microsoft Q&A