Trapped in an Authenticator Loop

Your Mac and Teams are not causing the loop; the work account is requesting an Authenticator registration that is no longer available on the iPhone. Reinstalling the app or changing browsers cannot restore it. The earlier reply correctly points to an administrator reset. An officially supported recovery path is for your employer's Entra administrator to verify your identity, remove the obsolete Authenticator method, and issue a Temporary Access Pass. An Authentication Administrator can do this under Entra ID > Users > your account > Authentication methods. Use the time-limited pass to sign in at Security info, register Authenticator on the iPhone, test the new method, then remove the old entry. If “Use another verification method” offers a working phone, security key, or recovery method, use that first. Otherwise, there is no safe user-side bypass; escalate through your manager or Microsoft 365 tenant owner until an authorized administrator performs the recovery.