Microsoft 365 features that help users manage their subscriptions, account settings, and billing information.
It sounds like you're stuck because it's asking for a code from the same Authenticator app you can't access. Since you're the admin, try signing in to Microsoft 365 from a web browser and see if you can reset your verification method or add a new one. I'd also check your spam folder for the email code. If you're still locked out, you'll probably need to contact Microsoft Support to recover access to your account.