A cloud-based identity and access management service for securing user authentication and resource access
Do you know if there are any other administrators in your Microsoft 365 tenant?
If you're unsure who the Global Admin is within your organization, you can find guidance on locating them here: How do I find my Microsoft 365 admin? - Microsoft Support
Please contact your administrator or another administrator in your organization and ask them to reset or revoke the affected MFA methods for your account by following the steps in this article Manage authentication methods for Microsoft Entra multi-factor authentication - Microsoft Entra ID …
Once the MFA methods have been reset, you'll be prompted to configure a new multi-factor authentication method the next time you sign in. At that point, you can register the Microsoft Authenticator app again on your device.
If this account is the only administrator account in the tenant and no other administrator can access the environment, the official recovery path is to contact Microsoft Support for tenant recovery assistance and identity verification. Microsoft's Data Protection team can help restore administrative access after ownership of the tenant has been verified.
I would recommend doing so, as it is often the fastest way to escalate tenant lockout scenarios. You can find the support phone number for your region here: Contact Microsoft Support
When calling the support number, you may first hear a recorded message lasting approximately 30 seconds (for example, suggesting that you visit an online support page). You can simply wait for the menu options to be presented. Typically, selecting "1" for business users and then "1" again for technical support will guide you to the appropriate support flow.
In some regions, the initial interaction may be handled entirely by an automated system. To help you prepare, below is an example of the questions you may receive and the recommended responses:
What kind of problem are you experiencing?
Answer: Authenticator
What product are you using?
Answer: Office 365 for business
Is this for an education or company account?
Answer: For companies
Are you an administrator?
Answer: Yes
Are there any other administrators in your organization?
Answer: No. I am the only administrator in the tenant.
Do you need a Service Request?
Answer: Yes. I need to open a support ticket. Please transfer me to the Data Protection team.
I hope this information helps you successfully escalate your request and regain access to your account. If you have any updates or additional questions, please feel free to reply to this thread. I will be happy to continue assisting you.