Accidental deleted account

Good day Pchandra, 

Just to gently clarify before going any further, this forum is separate from Microsoft Support. I don’t have the ability to access or investigate individual accounts or escalate the issue directly Microsoft Support because this is a user‑to‑user support forum. 

Since your MFA settings are still linked to your previous phone, they need to be reset before you can sign in again. As your administrator account remains active until November and you are the only administrator currently locked out, I recommend contacting Microsoft's Data Protection team as soon as possible, as they are responsible for helping restore access when the sole administrator account cannot be accessed. 

Please try locating the appropriate hotline for your region here: Customer service phone numbers - 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 can help restore access to your account and reset your MFA settings. You can then reset your account in the Microsoft Authenticator app using your current device or choose a different authentication method to sign in. I also recommend adding additional verification methods, such as a phone number, an email or a backup authentication option, to help ensure you can access your admin account if your primary method becomes unavailable in the future. 

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.)    

IVR: What problem is bothering you? 

Client: Lost access to the only administrator account and needs assistance restoring the accidentally deleted account. 

IVR: What product do you use? 

Customer: Microsoft 365 E5 Developer. 

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 Teams. 

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 

Additionally, here are some reference threads where I have helped other admins contact Microsoft Support, which may give you confidence in using these options: 

Global Admin locked out after iPhone replacement - Authenticator MFA cannot be re-registered 

Sole Global Administrator locked out 

I hope this helps point you in the right direction. If you have any updates or additional questions, feel free to reply back and I'll do my best to assist further. 

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