I am the only Global Administrator for our Microsoft 365 tenant. I am locked out of the admin

sturla Magnússon 0 Reputation points
2026-09-16T20:47:50.44+00:00

The only Global Administrator, [Moderator note: Personally Identifiable Information removed]@sfsmidir.is, is locked out because SMS MFA verification fails. [Moderator note: Personally Identifiable Information removed]@sfsmidir.is can sign in but has no administrator role. Please assist with sole Global Administrator MFA lockout and tenant recovery.

“I am the only Global Administrator for our Microsoft 365 tenant. I am locked out of the admin account because MFA verification is failing. SMS verification fails with error code 399287. There is no other administrator who can reset my MFA. I need help recovering access to the tenant and resetting MFA.”..

Microsoft 365 and Office | Subscription, account, billing | For business | Other
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  1. sturla Magnússon 0 Reputation points
    2026-09-17T13:33:38.1266667+00:00

    I created a new Enterprise account, which comes with a one-month free trial. I’ve already submitted a support request. It can take up to five days to get a response, so for now all I can do is wait and hope for the best ;) thx

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  2. Kai-L 19,145 Reputation points Microsoft External Staff Moderator
    2026-09-16T21:11:46.6233333+00:00

    Dear sturla,

    I'm sorry to hear that you are locked out of the administrator account because the registered phone number is no longer available. I understand how urgent this can be when the account is needed to manage your organization's Microsoft 365 services. As a forum moderator, I genuinely wish I could directly reset the MFA method on your account for you. Unfortunately, my role here is limited to providing general guidance and steps you can apply from your side. I am not able to reset MFA, recover admin access, or make changes to your Microsoft 365 tenant. That said, I will do my best to provide a clear path forward. 

    First, when the sign-in prompts for the Authenticator code, look for the option "I can't use my Microsoft Authenticator app right now" and choose an alternative method, such as SMS, phone call, alternate email, or a saved backup code, if any of these were set up previously. 

    Unfortunately, if you're the sole administrator in your organization and no alternative verification methods are available, you will not be able to resolve this on your own. You will need to contact the Microsoft Data Protection team directly for assistance. This team has the tools to verify your identity and help you regain access to your account. For business accounts, the best way to reach them is by phone. You can refer to this article to see the customer support phone number for your region. 

    Customer service phone numbers - Microsoft Support 

    Here are some tips and a sample response to help you navigate the Interactive Voice Response (IVR) system more effectively: 

    In some countries the call is handled by an automated system, which tends to cut people off if the answers do not match what it expects. Here is a flow that generally works better: 

    IVR: What kind of problem do you have? 

    You: Authenticator 

    IVR: What kind of product do you use? 

    You: Office 365 for business. 

    IVR confirmation: education or business account?  

    You: For Business 

    IVR: Are you an administrator? 

    You: Yes. 

    IVR: Is there another administrator in your organization? 

    You: No. 

    IVR: Do you need a... service request? 

    You: Yes, please connect me with the Data Protection team. 

    Kindly note that you may need to repeat this process a few times, availability can vary based on local business hours, and the term "Global Admin" should be clearly mentioned during the call. 

    Alternatively, if reaching support by phone is not possible, you can also create a free trial tenant and submit your request from there. To set up a new tenant, follow these steps: 

    Visit the Office 365 Enterprise plan and pricing comparison page, choose Basic plan, and click "Try for free" to start a free trial. 

    Follow the guided setup process to create your new trial account. 

    Once the new tenant is created, you should be able to access your support portal and submit your ticket. 

    Sign in to the Microsoft 365 admin center 

    Go to Show All > Support > New Service Request

    In the request, explain your situation in detail. 

    The support team will guide you through the identity verification process to help you regain access to your account. 

    Important Notes: 

    This new test tenant doesn't give you access to your original locked tenant's data or settings. It only serves as a temporary means of contacting Microsoft support. 

    Be prepared for Microsoft to want to verify your identity and admin privileges from the previous tenant. 

    The processing time may be longer due to contacting support from another tenant. 

    Remember to cancel the trial subscription as soon as your original account is restored to avoid unwanted charges. 

     

    I truly hope you get this resolved swiftly. Please know that even though I cannot directly intervene, pointing you toward the correct, specialized support is genuinely the most effective help I can offer from my position. Please let me know if you need anything else. Wishing you all the best. 


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