Global Admin locked out – Unable to access Microsoft Authenticator, request tenant recovery via DNS verification

Hello Sirilak Mooldee

Thank you for posting your question in the Microsoft Q&A forum.

According to your description, I'm sorry to hear about the trouble you're facing with your institutional accounts. 

Since you are the only admin, you will need to contact Microsoft’s Data Protection team. This team has the authority and specific security procedures to verify your identity as the legitimate owner of the account and then reset your MFA settings from their end. Please try to find the related hotline number for your region to call the frontline and let them raise a ticket for you: Customer service phone numbers - Microsoft Support    

Here are some tips and an example of a prompt to help you navigate the IVR more effectively:  

(When you call the support number, you may hear an introduction of about 30 seconds such as "you can visit the link...". You can ignore this introduction and wait until you are presented with the options. Then press "1" as a business email user, and again "1" for technical help.)    

In some regions, the initial interaction may be automated, so here’s a general idea of how the conversation might go to help you prepare:      

• What kind of problem are you experiencing?         
• Answer: Authenticator         
• What products do you use?         
• 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 admin in my tenant          
• Do you need a... Service request?          
• Answer: Yes. I need to create a ticket. Please send me direct to the Data Protection Teams.      

If Support Is Unreachable:     

If you are unable to reach a support agent by phone, there is an alternative approach that can help you resolve your issue quickly. You can register for a trial subscription by signing up through this link: Compare All Microsoft 365 Plans | Microsoft.  

Please note that creating a trial tenant is completely free, so you will not incur any charges as long as you cancel the trial after your issue is resolved. 

Once your trial tenant is created and registered, log in to the Microsoft 365 Admin Center. From there, select “Help & Support” and submit a support ticket. In your request, please mention that you need to speak with the Data Protection team on behalf of your previous tenant. This method allows you to connect directly with a support agent through the admin portal and ensures that your request is handled promptly. 

Please remember to cancel the trial subscription once your issue is resolved to avoid any unintended charges.  

I understand this may feel like an extra step, but it is the most effective way to get assistance when direct phone support is unavailable. If you need any guidance during this process, feel free to reach out, I'm here to help.  

Please understand that as forum moderators, we do not have the tools or sufficient access to make changes to user accounts, including logging in, resetting passwords, or modifying access rights. For your security, only Microsoft Support can assist with these requests. 

Warm regards,

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