linking is done on EA's side, you have to work with them to get it unlinked. good luck with it.

you may want to do a refund on the game, then make a new steam account and buy the game on the new account.

Contact EA support. That issue is on their side, not steam's side. Steam is not in charge of your EA Account. You are. As Wolf Knight said, if you do not want to take the time to try to recover it, just refund the game and make a new account so you can link a new EA ACCOUNT to it. Just remember to write the password and stuff down so you do not forget. Always do this. I use a password notebook next to me. IT helps in case you forget xxx account information. I notice alot of people forget their password stuff, so i always suggest this info to everybody.