Office 365 License

Good day Jeffrey, 

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. 

An Office 365 E3 Developer subscription can use two different accounts: 

1/ The Developer Program account, which is the personal, work, school or Visual Studio account you originally used to join the Microsoft 365 Developer Program. 

2/ The tenant administrator account, which was created when the developer sandbox tenant was provisioned. 

Additional information is available in the following resource: Microsoft 365 Developer Program FAQ | Microsoft Learn 

The appropriate solution depends on the reason you cannot sign in. Please follow the option that matches your situation: 

Option 1: Verify the correct account 

Open the Developer Program dashboard: https://aka.ms/DevProgramDashboard  

Sign in with the account you originally used to join the Microsoft 365 Developer Program. 

Don't use the tenant's onmicrosoft.com account on this page. 

Locate your developer subscription and note the administrator account shown there. 

Open https://admin.microsoft.com and sign in using that administrator account. 

Option 2: Reset your password 

If you have forgotten the password or the password is no longer accepted, try the Microsoft password reset page. 

Go to the https://passwordreset.microsoftonline.com/. 

Enter your email address and complete the verification steps. 

Create a new password, then try signing in to the Developer Program dashboard or the Microsoft 365 admin center (with the admin account). 

This option works only if self service password reset was previously enabled and you can access one of the registered verification methods. 

Option 3: Check the subscription status 

After accessing the Developer Program dashboard or the Microsoft 365 admin center, verify whether the developer subscription shows Active, Expired, or Deleted. If the subscription has been deleted, the original tenant cannot be recovered and a new developer subscription must be created if you are still eligible. 

Option 4: If authentication is blocking access 

If you're the only administrator and cannot complete the sign in verification process, 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 team can help restore access to your administrator account so you can update your password or MFA settings and proceed with the domain or tenant removal. 

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 admin account. 

IVR: What product do you use? 

Customer: Office 365 E3 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 

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 wish I could help more directly, but as a fellow user in this community, providing these steps is the best support I can offer. 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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