Issues with sandbox tenant and my personal outlook.com account
A few days ago, I did a MS Learn learning path which included a sandbox.
Today I wanted to start my Outlook desktop app, and suddenly the app asked my password. The password that I filled in, was wrong. After a few tries, I found that he want the password from the account that I setup during the sandbox. That's the same email address. So I logged in the Sandbox Azure portal and saw that my own domain was verified, without any conformation from my side, at the onmicrosoft.com tenant which is created during the sandbox with a B2B connection. So, there is a spooky Azure AD tenant, with my MSA-email as domain and member, without any global admin roles. I can't do anything in this tenant.
Please Microsoft Learn, please fix this for me. The issue now is, I can't login to my Outlook desktop app, can't setup any new W10 devices with my Microsoft account, etc. One big issue. Al I want is to delete my domain/email from the tenant which is blocking my Microsoft account.
Long history, I have my own domain at outlook.com. Back in early days, 2010, you could connect your own domain into Windows Live Admin Center and you had your own domain with Outlook.com. My MSA is then also user@domain.tld instead of username@outlook.com.