Sole Global Administrator locked out — MFA Error 399287 — Phone Reputation block

Hello Inna,

While waiting for the appropriate assistance, you can try the methods I provided to reach out to the Microsoft Data Protection team for further support with removing the bad reputation and resetting your account.

(As I am not authorized to support you directly, I can only provide you with all the information I have available.)

1/ Contacting Microsoft Data Protection team by phone support

In this situation, the Microsoft Data Protection team has tools and processes in place to verify identity and regain access to administrator accounts.     

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

If you can use English, you may prefer these numbers:

(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 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.

Please try "2 or 3"times until you can reach out to an agent.

2/ Another work around

If you still cannot reach to agent, there is still a workaround, you might consider registering for a new tenant by signing up for a trial subscription. 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.   

For detailed guidance, to set up a new tenant, please follow these steps:    

• Visit this following link and choose any plan and click try for free to start a free trial: Microsoft 365 Business Plans and Pricing | Microsoft 365
• 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 without further issues 

Ticket Support: In the Microsoft 365 Admin Center->Support->Help & Support. You can raise support ticket In Microsoft Admin Center by this link:

https://admin.microsoft.com/#/support/requests 

Tips: You can switch off the Support Assistant as shown in the screenshot, then type "Contact Support" into the search box and select "Contact Support" or the "earphone symbol" above..

• Choose "Phone" support and fill all the details of this issue.
• Click "Contact me"

After completing them, you will receive an email appointment for a meeting to review this issue professionally together.

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

Wish you all the best!