Sole Global Admin locked out of Microsoft 365 – MFA error AADSTS500121 – How to contact Data Protection Team?

Dear @Flavia Natalie,

Good day! Welcome to Microsoft Q&A forum!

First of all, I would like to clarify that this is a community forum where users help one another. No one here, including myself, has access to your Microsoft 365 tenant, account details, billing information, or authentication settings.

You can refer this thread from Moderator for your reference:

• URGENT: Sole Global Administrator locked out by MFA + unable to update blocked payment card

About this situation, you are receiving error AADSTS500121, which generally indicates that a required MFA challenge could not be completed. Since the available verification method is Microsoft Authenticator and you do not have access to it, the sign-in process cannot be completed.

Regarding your questions:

1/ How can a sole Global Administrator contact the Microsoft Data Protection Team without being able to sign in?

• If you are the only administrator and cannot satisfy the MFA prompt, the usual path is to contact Microsoft's frontline support and have your case routed to the appropriate team (Data Protection Team) for account recovery and ownership verification.

2/ Is there an official way to open a support case without creating a new tenant?

• Yes. You can try contacting Microsoft Support by phone using the business support number for your region.
• If phone support is unable to create a case directly, another option is to have an administrator from a different Microsoft 365 tenant open a support request on your behalf, or create a temporary trial tenant to raise a support ticket from there solely for contacting support (you could cancel the trial subscription once you have regained access to your sole admin account)

3/ Can Microsoft assist with resetting MFA registration after verifying ownership?

• Please note that this is a community forum where users help one another. I do not have control over user accounts, including login issues, password resets, or access changes.
• Data Protection Team can review account recovery requests and ownership verification documentation submitted during the support process

Therefore, could you kindly check if you know someone with Admin rights to a Microsoft 365 Business tenant that could help raise a support ticket on your behalf (with your contact information in the ticket's description so that the Data Protection Team could reach out to you)?

If that option is not available, I strongly recommend creating a new tenant account and submitting your request from there.

To set up a new tenant, please follow these steps: 

• Visit Compare Office 365 Enterprise Pricing and Plans | Microsoft 365, choose any plan and click try for free to start a free trial.    
• Follow the guided setup process to create a new account for a new tenant. 

Once your tenant is created, you should be able to access the support portal and submit your ticket referencing your locked account without further issues.

In the ticket's description, you could refer to this message

"Hello,

I am currently locked out of my Microsoft 365 tenant because multi-factor authentication is enforced, and I am unable to complete the verification process. I am the only global administrator for this tenant, which means I cannot access my account or the Microsoft 365 Admin Center.

To resolve this, I have created a new tenant and would like to be connected with the Data Protection Team to verify my identity and assist with regaining access. I am available to provide any required documentation or verification to support the recovery process."

Ticket Support: Log in the Microsoft 365 Admin Center using the newly created trial admin account (not the currently locked one) > Support > Help & Support. You can raise support ticket at: https://admin.microsoft.com/#/support/requests   

When you open a support ticket, please make sure to turn off the Support Assistant (AI) in the help panel.  

Several customers have reported issues when the Support Assistant is turned on  the system sometimes fails to display the “Contact Support” option.  

As shown in the screenshot, simply switch Support Assistant > Off, then type your issue description.  Once the AI is off, the “Contact Support” button will appear normally, allowing you to submit a ticket directly.  

• After clicking on "Help & Support" button, you can type "I need agent support via phone or email". After that, you can click on "Contact support" 
• Choose contact method: "Phone" 
• Fill all the information in this contact support details, please describe your situation carefully so they will have enough information to help you. 
• Finally, click on "Contact me"
• After completing them, you will receive an email appointment for a meeting to review this issue professionally together. 
• For more details, you could refer to this article: Get support for Microsoft 365 for business 
• This new trial tenant will not give you access to any of the data or settings in your original locked tenant. It is solely a temporary means to contact Microsoft support.   
• Be prepared for Microsoft support to ask for verification of your identity and administrative rights for the locked tenant.   
• The resolution time might be longer as you are contacting support from a different tenant.   
• Remember to cancel the trial subscription for the new tenant once your issue with the original account is resolved to avoid any unintended charges. You can typically do this within the Microsoft 365 Admin Center under "Billing" > "Your products."

For references:

• How to troubleshoot Microsoft Entra sign-in errors

If you've run into any challenges or if there's anything further that I can help with, please don’t hesitate to let me know. Any updates you’re able to share would be greatly appreciated.

Thanks for your time and attention! I look forward to hearing from you.