Capital One bought out my old bank. I should have

Capital One bought out my old bank. I should have closed my account right away, but I didn't and now I am paying for it. I attempted to close my account a few weeks ago after being charged an "annual fee" for the second month in a row. I thought the account was closed, but today I received ANOTHER letter from them saying I owe the annual fee plus interest. I don't know how dumb they think people are, but I definitely can't wait to rip them a new one. And write a nice letter to the state Attorney General. Screw you, Capital One!!