Not able to login to the admin without authenticator app

Good day Outdo and I’m sorry to hear about the difficulties you’re experiencing.  

The MFA loop occurred because the authenticator app was deleted and reinstalled. This removed the existing MFA registration from the device, so the admin account can no longer complete the verification process. 

Based on what you've described, the next steps will depend on whether there are other administrators in your organization who can access the tenant. 

If another administrator is available, I'd recommend contacting them and asking if they can reset the password and MFA settings for the affected account through the Microsoft Entra admin center. This is usually the quickest way to regain access. 

For reference: Manage authentication methods for Microsoft Entra multifactor authentication - Microsoft Entra ID | … 

If you're the only administrator and you've been locked out of the account, you'll need to contact Microsoft's Data Protection team for assistance. They are the only team authorized to help recover access in situations involving the sole administrator account. 

You can find Microsoft's support numbers here: Contact Microsoft customer support | Microsoft Support 

When contacting Microsoft, be prepared to verify your subscription ownership by providing details such as your organization name, billing or payment information, registered phone number and alternate email address. 

Once your identity is verified, the privacy team will be able to reset your MFA settings. You can then reset your account in the Microsoft Authenticator app using your current phone number or choose a different authentication method to sign in. 

Tips for navigating the IVR:  

(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, an automated voice system is used. Example of a dialogue: 

IVR: What problem is bothering you? 

Client: Lost access to the only admin account. 

IVR: What product do you use? 

Customer: Office 365 for business. 

IVR: School or Business account? 

Client: Business account. 

IVR: Are you an administrator? 

Client: Yes. 

IVR: Is there another administrator in your organization? 

Client: No. I am the only admin in my tenant.     

IVR: Do you need to create a support ticket? 

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

In case you are unable to contact the frontline support: 

Consider signing up for a trial subscription to create a new tenant. Visit Microsoft 365 Business Plans and Pricing | Microsoft 365. 

Once the new tenant is set up, you can access its admin center and submit a support ticket through Microsoft 365 admin center > Support > Help & Support to contact the Data Protection team regarding the previous tenant. Please remember to cancel the trial subscription after your issue is resolved, as this will help you avoid any accidental billing. You may prefer the following resource for detailed instructions: Cancel your Microsoft business subscription in the Microsoft 365 admin center | Microsoft Learn 

If your organization's subscription is from a partner or reseller: Contact the reseller's support provider to help open a service request on behalf of you instead. 

I hope this helps point you in the right direction. If you have any questions or need further support, please don’t hesitate to reach out at any time. 

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