Dear Collin,
Good day!
Thank you for posting to Microsoft Community. We are glad to assist.
As per your mentioned description about "Stuck in a authenticator app loop" My sincerest apologies for the inconvenience this might be causing you. I would like to share some information with you, since we have dedicated support team for Microsoft Authenticator related query. So, we would recommend you to kindly post your query to Microsoft Authenticator support Forum via Microsoft Authenticator - Microsoft Q&A Engineers who are dedicated into Microsoft Authenticator with rich experience and more resources can then assist efficiently. We believe they would conduct in-depth research on the problem you encountered and provide you with more professional assistance.
In the meantime, kindly note this is very sensitive and should not be discussed here in a public forum which is accessible to all Microsoft customers. We value your organization’s security and privacy; If there is another Global Administrator (GA) in your organization, kindly contact him/her to reset the Authentication method for your account. Admin can do it by follow Manage user authentication options. (if you are not sure who is your admin, can refer this How do I find my Microsoft 365 admin? - Microsoft Support).
If you are the only Global admin, 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 and regaining access to your account. Thank you so much for your precious time and co-operation. Have a nice day!
Best regards,
Inema |Community Moderator