My outlook account no longer exists despite recent activity

A few months ago I made the switch from Hotmail to Outlook, and added a new primary alias. This alias was working fine until last week when I tried to log in, but I was told that my account no longer existed. I regularly used this account so it could not have been deleted due to inactivity. I cannot log in to any service using either my old Hotmail address or my primary alias, as I am told my account no longer exists.

I registered a new Outlook account with my primary alias address to check if it was on a database. Because I was successful in creating my account, I assume my alias has been deleted.

Any help would be greatly appreciated.