Breach of Contract / Shocking Service

For the past 4 months I have not been charged the correct subscription with the amount becoming increasingly more until this last month I was charged more than double my subscription.<br> <br> When I did my upgrade in October I was told that my top up contract did not exist anymore and my only option was to take out the mtn 200 contract (even though this contract is unsatisfactory for me as I hardly ever use minutes or smses), I therefore made my billing limit at R0 so that I made sure that I couldn't go over my limit and would therefor not get billed extra amounts that I wasn't expecting.<br> <br> I have been into the mtn stores several times to ask them about these unexpected amounts.. Nobody has been able to tell me what was going on and I have been told on multiple occasions that I cannot be helped as the system is down. I tried to email the complaints line but after having one response to ask my cellphone number I haven't been contacted again even though I have sent multiple queries.<br> <br> I am so fed up with mtn that I don't actually want to be on this contract anymore.<br>