Telkom 2 years the same problem

We ordered an upgrade from capped ADS L , to 20 Meg uncapped fiber in May 1998. Since then we have been billed for both services, and every month we get a message saying we have reached our cap ,and we have to buy more data, so this would say we are still on the same ADSL line . I am trying every month for Telkom to actually switch off the ADSL and on the Fiber. On top of this we were billed for BOTH lines , and we queried this several times , and eventually we were supposedly credited for 18 months of over payment and we are supposedly in credit. So there three departments involved , billing,technical and sales. so when i query every single month for the last two years , why, since have I reached my cap , have I not been switched over from ADSL to fiber.? I get put into a circle... the technical team say I am on fiber, and refer me to sales who should remove the cap and upgrade my account to uncapped as part of the order originally, Sales in turn say they cant change the order to fiber , as billing must do. So every month after about two hours on the phone I am back at square one. I am not sure what package I am actually on , and every month I get told I have reached the cap. All I want is a 20 meg uncapped account, can Telkom provide this or should I change providers?