Without going into great detail, I am experincing serious difficulty getting "disconnted" from a local ISP.
The company is called "INTERNET CONCOURSE/CENTRAL OHIO INTERNET LINK".
Nearly a year after cancelling an internet access account by email and telephone with them I was sent a past due notice and a threat of collection procedures. Access to the account was never cancelled by them, and though not used it remained active as far as they were concerned.
Please don't do business with a company that operates like this. If you are, unfortunately, already engaged with them, document and record all that you can in order to assure your position upon termination of service.
Registered, signature required letters on all corespondence would not be a bad idea either.