Locked out of M365 Developer Tenant (Sole Global Admin) due to lost Authenticator app - Request MFA Reset

Hi Thái,

Welcome to the Microsoft Q&A forum.

Because you are the only Global Administrator in the tenant, you will need to contact the Data Protection Team through Microsoft Support's hotline to request an MFA reset.

Please look up the appropriate support hotline for your region and call Microsoft's frontline support. Then, request that they create a support ticket for you through the following link:

Customer service phone numbers – Microsoft Support.

Please note that moderators on this forum do not have the authority to directly intervene in user accounts, especially for issues related to:

• Account sign-in
• Password resets
• MFA authentication
• Changing or restoring access permissions

Tips for navigating the IVR system (automated phone support)

To help you navigate the IVR system more effectively, please refer to the guidance below:

• When calling the support number, you may hear an introduction for about 30 seconds (for example: "You can visit the link..."). You can skip this part and wait until the system presents the available options.
• Then:
•  
  • Press "1" for a business email account.
    • Press "1" again to select technical support.

In some regions, the initial interaction may be fully automated. Below is a sample dialogue you can prepare in advance:

• What kind of problem are you experiencing? Answer: Authenticator
• What products do you use? Answer: Microsoft 365 for Business
• Is this for an education or company account? Answer: For a company
• Are you an administrator? Answer: Yes
• Are there any other administrators in your organization? Answer: No. I am the only administrator in my tenant.
• Do you need a service request? Answer: Yes. I need to create a support ticket. Please connect me directly with the Data Protection Team.

During the call, you may be asked to provide subscription-related information such as:

• Company name
• Billing information
• Phone number
• Alternate email address

This information helps the Data Protection Team verify your identity and securely assist you in restoring access to your account.

I hope this information is helpful. Please follow these steps and let me know if it works for you. If not, we can work together to resolve this.   

Thank you for your patience and your understanding. If you have any questions or need further assistance, please feel free to share them in the comments on this post so I can continue to support you.

I look forward to continuing the conversation.

If the answer is helpful, please click "Yes". 

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