Unauthorized user has access to my account

A week ago or so, someone connected/linked their apple ID to my madden mobile account. I strictly play on android. I have an ea account + my Google play both linked to the account. However because I don't have access to the users Apple ID, obviously I cant unlink it.  I asked them to stop playing on my account but they log in everyday. Am I screwed? I don't need help recovering the account. I can log in just fine. But how do I prevent someone else from keeping logging in if they already linked their 3rd party app to my account. What can support do? I started a ticket and they closed it without a response.