Hi, Bernardo
Good day!
Thank you for posting to Microsoft Community. We are glad to assist you!
According to your description, I'm sorry to hear about the frustrating situation you're facing with the Microsoft Authenticator app.
As specific support channel resource for certain different support scope and attributes. Since we're focusing on Exchange Online, we're afraid that we could not give you an appropriate suggestion here. For this given issue is relates to the Microsoft Authenticator and we do not have enough testing environment and fixing tool for this so this is really out of the scope of support in this community - Microsoft Authenticator App Tech Forum.
Microsoft Microsoft Authenticator tech support experts in here who are responsible for consult about this given issue and will provide you further help.
In addition, another option for you that you can contact your administrator and reset the MFA for your account -Gerenciar métodos de autenticação para autenticação multifator do Microsoft Entra - Microsoft Entra ID | Microsoft Learn.
Note: Please be kindly to understand for our community team that we do not have the authority to access into the backend.
Thank you for your precious time and your understanding would be highly appreciated.
Sincerely,
Alex | Microsoft Community Moderator.