Text verification does not work to sign in

Hi @Prenissa Sookdiyal,

Thank you for reaching out to Microsoft Q&A forum.

The error code 399287 and the inability to use text verification (with no other MFA options available) usually means your account is locked behind Multi-Factor Authentication (MFA) and the configured method is either broken or inaccessible. Since you’re the only admin, this can block access to the Microsoft 365 Admin Center.

If you are the sole Global Administrator on the tenant, please follow the steps outlined below to proceed with account recovery and regain access. 

Option 1: Contact Microsoft Data Protection Support by Phone (Primary Method)   

To regain access to your admin account as you can't access the Admin Portal, you can try reaching out to our Global Customer Service phone to raise a request for resetting your authentication method here: Customer service phone numbers - Microsoft Support. During the call, request to speak to an agent, and share with them every detail related to your query and also mention that you are the only admin lost access to your account. This should allow you to contact the appropriate team so you can solve this incident as soon as possible.  

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

In some countries, it is an automated conversation like:  

IVR: What kind of problem are you concerned about?        

You: Authenticator.        

IVR: What kind of product do you use?        

You: Office 365 for business.        

IVR confirmation: education or company account?        

You: For companies        

IVR: Are you an administrator?        

You: Yes.        

IVR: Do you have another administrator in your organization?        

You: No.        

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

You: Yes. I need to create a ticket. Please send me direct to the Data Protection Team.   

Option 2: Create a Temporary Account (Trial Tenant) to Submit a Support Ticket (Alternative Method)  

If you still cannot reach to a live agent, there is still a workaround, you might consider registering for a new tenant by signing up for a trial subscription via this link Microsoft 365 Business Plans and Pricing | Microsoft 365. This would allow you to create a new tenant following the prompts provided. Once set up, you can access the admin console of the new tenant and submit a support ticket requesting to speak with the Data Protection team on behalf of your previous tenant.

Please note that forum moderators do not have access to user account settings and cannot assist with logging in, resetting passwords, or changing access rights. While we do not have access to internal systems or administrative tools required to resolve account-specific or backend-related issues but we’ll continue doing our best to support you within the scope of our responsibilities.         

I hope this helps you regain access to your account quickly. I'm glad to assist and truly hope the information provided has been useful. Please feel free to reach out anytime if you need further assistance.  

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