Reset MFA after lost of phone when I am the only administrator in my o365 tenant

Question

I lost me phone hence lost MFA and I am the only administrator in my o365 tenant.
I tried to call 0800 800 004, but the answering system is malfunctioning and could not event get my phone number right after 20 min !
I can log buisness support online case since that requires log in (obviously I cant log in without MFA).
When I use phone text as alternative it pops up error message

I am stuck in the middle of nowhere and cant move further, please help me !

Moved from Microsoft 365 and Office | Access | For business | Other

Answer 1

Hi @Neil Xu,

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

I’m very sorry to hear about your situation. Regarding that you’re unable to log in to your global admin account.  

If you don't have any other admin account in this situation, the Microsoft Data Protection team has tools and processes in place to verify identity and regain access to administrator accounts.    

Please note that forum moderators have no control over user accounts, especially when it comes to logging in to your account, resetting your password, changing your access, etc.    

Therefore, If you are the only administrator in your organization,  then you need to involve Microsoft data protection team. Please try to find the related hotline number to call the frontline let them raise a ticket for you: Customer service phone numbers - Microsoft Support 

*(Important Note: Depending on your country or region, 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 countries, this is an automated conversation: First, when you call the hotline, they will ask you what kind of problem you are struggling with.    

Answer: Authenticator.    

A: What products do you use?    

B: Office 365 for business.    

Verification: Education or company account?    

B: For companies    

A: Are you an administrator?    

B: Yes.    

A: Are there any other administrators in your organization?    

B: No.    

A: I need one.... Service request?    

B: Yes    

If your organization's Office 365 Business/Education subscription is from a partner or reseller, and the global administrator is unable to open a service request on your end, contact the reseller's support provider to help open a service request on behalf of you instead.    

Alternatively, you can try set up a new trial tenant and submit your support request:   

1. Visit the Microsoft 365 Enterprise Plans page: Go to Compare Office 365 Enterprise Pricing and Plans | Microsoft 365.   
2. Choose a plan and start a free trial: Select any of the available plans and click "Try for free" to begin the trial setup process.   
3. Follow the guided setup: Complete the steps to create a new Microsoft account and a new tenant. This will be a separate and independent Microsoft 365 environment.   
4. Access the Microsoft 365 Admin Center: Once the new tenant is created, navigate to https://admin.microsoft.com/.   
5. Go to Support: In the left-hand navigation menu, click on "Support" and then "Help & support."   
6. Raise a support ticket: Describe your issue in detail. Crucially, you must clearly state that you are locked out of a different, pre-existing Microsoft 365 tenant where you are the administrator. Provide the following information about your locked account:    
   • Your administrator account email address for the locked tenant.   
   • The domain name of your locked tenant    
   • Any error messages you are receiving.   
   • Details about the authentication issues you are experiencing.   
   • Confirmation that you are the administrator of the locked tenant.   
7. Submit your ticket: Follow the prompts to submit your support request. You will likely receive a ticket number for tracking.   

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.  

Important notes:    

• 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."   

I hope these steps will help resolve your issue. If you need further assistance, we are always here to help.     

Thank you again for your time and understanding. While my initial response may not resolve the issue immediately, I’d like to gather more details about your situation so I can assist you more effectively.    

I really appreciate your patience, and I’m here to help. Looking forward to your response.   

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Answer 2

Because the phone with Microsoft Authenticator is lost, SMS verification fails, and there are no other admins in the tenant, the only supported way to reset MFA is through Microsoft’s Data Protection/Tenant Recovery process.

Use these steps:

1. Call Microsoft global customer service for business support using the regional number listed under Customer service phone numbers - Microsoft Support.
2. When the IVR/agent asks about the issue, clearly state that this is an Authenticator / MFA lockout and that this is for Office 365/Microsoft 365 for business.
3. Confirm all of the following during the call:
   • This is a company/organization account, not a personal Outlook.com account.
   • The caller is the only global administrator for the tenant.
   • MFA is required and the only registered method (Microsoft Authenticator and SMS) no longer works.
   • It is not possible to sign in to the Microsoft 365 admin center to open a support ticket.
4. Ask specifically to be transferred to or have a ticket opened for the Microsoft Data Protection team (sometimes called Tenant Recovery/Data Protection Support) so they can verify identity and reset the MFA registration for the admin account.
5. Be prepared to provide tenant and identity proof details requested by the Data Protection team (admin UPN, tenant domain, billing info, etc.). After verification, they can clear the MFA methods so new ones can be registered at next sign-in.

If the phone system continues to malfunction or never reaches a live agent, an alternative is:

1. Create a new temporary Microsoft 365 tenant by starting a free trial from the Microsoft 365 Business/Enterprise plans page.
2. In that new tenant, sign in to the Microsoft 365 admin center as the new trial’s global admin.
3. From Support → Help & support, open a support ticket.
4. In the ticket, explain that the request is for a different, existing tenant where the admin is locked out due to MFA and is the only global admin. Provide:
   • Locked tenant’s primary domain.
   • Locked admin’s sign-in address.
   • Error message (“Sorry, we’re having trouble verifying your account. Please try again.”) and that SMS and Authenticator both fail.
5. Ask support to escalate to the Data Protection/Tenant Recovery team for MFA reset on the original tenant.
6. After the original tenant is recovered and MFA is reset, cancel the trial subscription on the temporary tenant to avoid charges.

There is no self-service way to bypass or reset MFA for the only global admin; involvement of Microsoft support/Data Protection is required.

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References:

• I have a Micrsoft business account and I am the admin and the only user registered under this account. I can't log in because i have replaced my phone and the authenticator doesn't work. - Microsoft Q&A
• Requesting a Tenant Admin MFA Reset - Microsoft Q&A
• Microsoft authenticator sending me into a spiral - Microsoft Q&A
• "Account verification system is having trouble" error message when you try to sign in by using a work or school account