TELKOM - Unauthorized billing and handover

About 3 years ago we enquired at Telkom for an ADSL line in Brakpan North. Telkom's response was that they would not be investing in the area. Even now there are no telephone lines in that area. Ever since Telkom has billed us for something that they haven't even installed! Threats of being handed over are really starting to work on my nerves. As soon as you explain the situation to the one collector, it gets handed over to another company. This needs to be stopped immediately, or I will have to take it further. Nobody can supply us proof of the contract signed, nor a usage account because THE THING THEY ARE CHARGING FOR DOESN'T EXIST.