Locked out of my account

I’m currently locked out of my EA account that is linked to my Xbox account. Whenever I try to play battlefield or dead space the game will ask me to sign into EA with an email I no longer have access to, it tells me that it’s reset my password and to sign into my email but I can’t because it’s been deactivated. I’m not sure what to do as I’ve tried going through customer service to link that account with this one that I have access to but they were unable to prove that the account is actually mine. I have a list of purchases made proving that the account is mine so I’m completely lost on what more I can do. Please help me, I fear this may mean I won’t be able to use my main account and worst of all not be able to purchase future titles