Login account at startup that is listed as first 5 letters of Microsoft email account, does n

After I changed my laptop name, at startup I now get an account titled as the first 5 letters of my user folder name and it is also the first 5 letters of my Microsoft outlook email account. There is no such account. It requests a password, but of course there is not one. I tried several of my usual passwords, but none worked.

There is an alternate account option, which I use to log in, but it always opens with this non-existent account. l don't use password logins, so it's quite annoying.