The worst adsl provider I have ever experienced

Telkom service is terrible. I ordered a 10mg line from Telkom a month ago they came out to install and told me I can't get 10megs so I must down grade to 4megs that then took another week. Eventually I got connected but to my dismay I was receiving an average of 1meg line speed. I called Telkom numerously and got them to send out technicians and reset the port and everything and currently I have no internet and haven't had since Thursday last week. No I am fed up and want to cancel so I called in to do so and then just get transferred to a line that cuts my call every time. This is absolutely appalling service and now I still have to pay for it because they won't let me cancel. Telkom is the worst adsl provider I've ever dealt with and now I'm even unable to cancel this ****ty service. I refuse to pay for any of this as the issue is on their end. I want this line cancelled because I am not in the business of waisting my money on a company that has no clue what they are doing.