Can't access Dev Tenant

Dear @Fernando Ferrari,

Thank you so much for contacting Microsoft Q&A Forum, 

Based on your description, the error message displayed is: "This username may be incorrect. Make sure you typed it correctly. Otherwise, contact your admin." which has several reasons caused it: 

1.Incorrect username: the admin account you're using might not be the one associated with the Microsoft 365 Developer Program subscription. 

2.Account not provisioned: the subscription might not have been fully set up or assigned to the admin account you're trying to use. 

3.Tenant confusion: you might be trying to log in with an account from a different tenant than the one linked to the Dev Program. 

4.Expired or deleted subscription: if the subscription was inactive for a while, it might have been deleted or expired. 

5.Propagation delay: sometimes, after joining the Dev Program, it takes a few hours for the subscription to be fully provisioned. 

Therefore, I have several suggestions that you can check to see if they work for your issue: 

1.Verify the username: please double-check the email address used to sign up for the Dev Program. 

2.Check the Dev Program Dashboard to ensure the subscription is active and shows the correct tenant/domain. 

3.Try logging in via Microsoft 365 Admin Center: use the credentials shown in the Dev Program dashboard. 

4.Try to use browser with InPrivate/Incognito mode: this avoids cached credentials interfering with login.

5.Reset Password: if you are unsure about the password, try resetting it via the Microsoft 365 login page. Reset your password by clicking "Can't access your account?" on the login screen. Make sure you're using the correct account associated with your Microsoft 365 Developer Program subscription. If you're unsure which account is linked, you can check the Dev Program dashboard or contact Microsoft support for clarification. 

6.Contact Microsoft support: If all of the suggestions above fail, use the support link in the Dev Program dashboard to submit the issue. 

References: 

• I cannot login Microsoft 365 Developer Program Adminitrator Account - Microsoft Q&A
• Microsoft 365 Developer Program FAQ | Microsoft Learn 

Also, you can contact Microsoft Developer support: 

If the above step doesn’t help, you should post your issue on the official Microsoft Developer Community: https://developer.microsoft.com/en-us/community 

This is often more effective than general support channels. 

I hope this information can help you to resolve this issue soon. 

Wish you a pleasant day! 

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