Screw Coinbase

Went and checked my account and coinbase stole almost $1500 worth of my ETH. They say I owed a balance which was from scammers that my bank reissued to me. Coinbase told me to go and take it up with the bank so I did and won. Now they take money from my account saying I had a negative balance. Is that something they can even do especially after they told me to take my issue up with my bank? Just take money out of my account?