EA StaffHi, unlinking accounts is currently only possible for Game Advisors. Please contact one of them via live chat or phone at https://help.ea.com/contact-us for further assistance.
Also on a general note, you should not create a new account, all your game entitlements are tied to your account and by simply changing to a new account you might lose access to all your previous games. If the email address for your account is no longer in use, you can get it changed to a new one by contacting a Game Advisor.
In this case I would strongly suggest to get the email address of your old account changed to a new one, instead of continue playing with the newly created Origin account.
This is not true, orgina will not make changes to your account unless you have access to your email. I haven't been able to play madden for years. EA is a terrible company
