Clueful contact at Microsoft needed

Apologies if this is off topic for NANOG. I need to contact someone at Microsoft who can correct problems with Microsoft accounts. I've been trying unsuccessfully to disavow a Microsoft account for some time. Note this an account someone has managed to associate with one of my email addresses. The Microsoft account does not belong to me. I've been unable to contact the account holder. I've been through their support site and system which has been singularly unhelpful (and also requires a Microsoft account just to contact anyone). It's clear the support people don't understand the problem. I mean, how does logging into the settings on my (non-microsoft) email account help solve a problem with the settings on a Microsoft account?