A cloud-based identity and access management service for securing user authentication and resource access
@Leonardo
Thank you for your time and patience throughout this issue and I apologize for the delayed response!
Since you can't login to the Azure Portal and it's only giving you the option of authenticating with the MS Authenticator App, can you select the Forgot my password? option during login.
1) Since you can't login via the Authenticator App to verify your identity, you can select User a different verification option.
2) You can verify your identity via Email, Phone/Text, or Authenticator App. If you don't have access to any of these options, you can select I don't have any of these.
3) If you have your Recovery codes, you can use them. Otherwise, you can select No.
4) After selecting No, you'll be redirected to fill out the Recover your account form to recover your Microsoft Account. For more info.

If you're using your onmicrosoft.com or tenant specific account, you can still select Forgot my password?, which will take you other authentication methods to login. If none of the above options work, you'll have to reach out to our Azure Data Protection team for further assistance - (866-807-5850).

For future reference, I'd also recommend creating and managing an emergency access account in Azure AD, this will help prevent being accidentally locked out of your Azure Active Directory (Azure AD) organization because you can't sign in or activate another user's account as an administrator.
If you have any other questions, please let me know.
Thank you for your time and patience throughout this issue.
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