Billed AGAIN for Internet ADD on bundle

I logged a complaint after receiving my invoice on 3 December. I was billed for Additional data of R488.60, which I have not requested. They said it was an error which should not have appeared, and would take about 72 hours to be resolved, and they issued me a case number ***0. Over a week later I called numerous times only to find out that they are still working on the case. I called again a few days ago which is almost A MONTH later, and was told that the debit order run has already been submitted and would only be rectified the following month. I received my new account for December today where NO credits have been passed for October and November and now it will also be for December! because I am STILL being billed for Additional data bundle!! This is totally unacceptable