Issues with coinbase

Recently ran into an issue with my 5 year old coinbase account and do not know where to turn. I have had a small account there since 2017. Recently retired and bought a fair amount of bitcoin. Soon after I received a vague email saying the there had been a hacking attempt to transfer my money out, and subsequently my account had been locked down for security. Being a noob, I assumed this meant neither I nor anyone else could touch my money. When I sold off a car I no longer needed last Friday I could not even transfer money into that account. Long story short, customer support says that they are conducting a review (for 7-10 days) and that there is no guarantee that I will be granted access to my account. And that all decisions are final. Since my money was in "Coinbase" , and not in a wallet, how do I go about getting my money??? Is it still mine? What are my legal options should they refuse to unlock my account? Thank you for any advice/clarification.