Account overcharge and bad attetude

I went to a Telkom branch this weekend wanting to pay my account for the second month as I was at Telkom the 1st month and they told me my account is not running yet. I have signed for a 4mb contract for R775 at Telkom and the contract stated that the line installation was free of charge on this contract. So as I was about to pay for my account they finally gave me a Telkom bill, to wich I was amazed to see that my bill is R2300 for 1 month and 23 days, the guy at the Telkom branch he told me just look at it before you come to me. That was 2 full months after they told me it would have been charged pro rata, plus they did charge me for some kind of service fee valued at about R700, which I could only think that it would be the line installation what they said they would not charge for. This is not the first time I am having difficulties with Telkom, with prior issues that the overcharged me for my previous line, and with the new line that no one even pitched to install my line and I had to call around and find out where they are, when they are going to come and what time, only after 3 appointments that they missed someone finally came around and installed it