No access to old EA account that’s linked to my current Xbox account.

I’ve had my Xbox account for probably 20 years now. It’s linked to my dad’s old email address that neither of us have had access to for years. I’ve been dealing with it, being unable to play games like NCAAF 25, A Way Out, and more online. Now, it’s not letting me access Battlefield 6, a game i just preordered for practically $100.  I’ve given up trying to get this account linked and nothing seems to help. I’m stuck as I have been for many years and don’t know where to go.