AOl internet service

I have tried to cancel AOL account Internet service stop using since April 2005.

I called 1 -888 - 889-7201 they transfer me to cancellation department then they put me on hold for several hours with out any help, than I hang up the phone. They keep sending a bill ever month which I paid for nothing. Please help me how to stop this unnecessary payment for which I don't use it.

Thanks!!