Cannot delete account - no longer have access to email + password keeps changing itself without my authority.

I changed my Apple ID email from '@icloud.com' to '@icloud.com' and since then bars have been placed over my microsoft account. Not only does it change the password for my account every single day(I have never in my entire life successfully logged into my account once using my password. Truthfully. I have to select 'Forgot password' every single time Which is the only password I have ever used for microsoft. And typically, now that I have lost access to my email, despite only changing my password back only yesterday, It's "incorrect" once again. I have contacted microsoft support on my browser, answered all questions correctly and provided the previous passwords I have used for my account. I was denied account support almost 30 seconds later with no reason provided.

I am an EU user, very seriously exercising my rights to full account deletion under Section 17 of the GDPR. Please contact me ASAP with any security questions or requests to prove I am the owner of this account.