Cancelling a credit card

[cacarr13]

I cancelled a credit card (in writing) in Dec.04.Received a letter confirming the cancellation, & advising me to make other arrangements for direct debits. In Feb.05 they paid an annual DD. I have now received a statement requiring payment. After a prolonged, fruitless telephone call to the credit card company I  was told  "the manager" would ring me back. Needless to say, I am still waiting. What can I do next? Can they make payments from a cancelled card? Is there some other way to insure that a card is really cancelled? How long could this continue? They accept that the card was cancelled, but insist they have done nothing wrong in making a payment! HELP!