Hello,
Thank you for posting in Q&A forum.
Based on your description of being asked for an authenticator code without multi-factor authentication (MFA) configured, it's possible that Azure AD automatically enabled MFA or that there's some form of MFA requirement in your account settings.
If you were able to reset your password, try resetting it again, which may help bypass multi-factor authentication. If you have another global administrator account in Azure Active Directory, you can use that account to disable MFA for the locked-out account or update MFA settings.
If you're the only global administrator and are completely locked out, you may need to contact Microsoft Azure Support for assistance. To do this, visit Azure - Microsoft Q&A Click "ask a question" in the upper right corner to submit a request.
I hope the information above is helpful.
Best Regards,
Yanhong Liu
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