Old deleted EA account linked to my Xbox account.

I'm pulling my hair out here, I have logged tickets before with no response..

I wanted to link my Xbox account to my current EA account, but got a message saying another EA account is already linked. That account shows something like "47******@deleted.ea.com" and I have no clue why or how that was done. Probably when I was young and dumb.

What can be done to get that account unlinked so that I can link my current EA and Xbox accounts?