Telkom faulty

Ive been with telkom since November of last year. Each time ive paid my bill on time and the correct amount if not more… last month i asked Telkom to explain why the app is saying R3000 for a bill when cellphone and wifi dont come to that price at max its supposed to be R2000 when i asked the lady she gave me some explanation that said basically its a summed up amount of what was the total of two month together and she said thats not how much i must pay and even got a telkom sms to say i needed to pay R1500, when i try calling each time i dont get a call back or even an explanation. Again this month now the bill says R3600 i now paid over R3700 which is way more than im supposed to pay and i get no explanation. Checking the statement it says amount brought forward? From what exactly when everything has been paid and oh they also took another R710 from my account when not once have they even taken a debit order?? What the hell is going on. This has made me so upset. I even want to cancel account completely