Xbox account is linked to a random (hacked?) EA account

My xbox GT which I've had for 14 years is randomly linked to someone else's EA account. I believe it to be nefarious as it's a .RU domain email, and I'm British.

I can prove that I own the GT obviously, but I see no way to unlink the XB account to the EA account on the Xbox side. Obviously I cannot unlink via EA side because I do not have access to the EA account. I have Gamepass so I assume someone may be leeching off of it somehow? 

I've never had my account hacked I don't believe but details have been "pwned" for other accounts with similar details, I've updated my XB details now so it's safe but I cannot find a way to unlink on my side at all.

Any help? Thank you so much! It makes me tentative to order BF6 until this is finished because I'm unable to access any EA games on my console currently as it requires me to log in!