Microsoft 365 features that help users manage their subscriptions, account settings, and billing information.
Dear oarai-omotenashi,
Good day! Thank you for posting to Microsoft Community.
I'm sorry to hear that you're having trouble finding a contact at Microsoft who can help you directly. May I please double confirm if account in question is the only admin account? if yes, I do understand your query here but, as your query related to admin account, and since we are belong to Microsoft Community site, our forum is available for public. Also, we have limited resource and privilege to examine account related scenarios. Moreover, since you are the only admin in your organization, admin account is relevant to the security of your organization, we value the security and privacy of your organization, so for your concerns, we sincerely recommend that you contact our dedicated data protection support team directly via phone support Find Microsoft 365 for business support phone numbers by country or region - Microsoft 365 admin | Microsoft Learn. They are the only responsible and privileged support team for account related queries. While phone call, press "1" as business email user and press "1" again as technical support. You also need to provide your subscription purchased information such as company name, billing information, phone number, alternative email address etc. So, our data protection team can assist you in resetting your multifactor authentication and once reset, you can add the authenticator again or choose other authentication method to sign into your account.
Thank you for your precious time and kind understanding. Have a nice day.
Sincerely,
Libeamlak | Microsoft Community Moderator