Cannot manage a simple contract renewal

My original Price Lock contract was supposed to end in October 2017. DSTV call-centre phones and sells me a new Price-lock contract. They then proceed to completely stuff up the billing so that I somehow get charged additional at the start of October. Please note my account has always been perfectly paid. 4 phone calls did not resolve. Spent 2 hours in Randburg on 6/11 trying to resolve. The Customer Service person who was "helping" disappears and does not come back after 40 minutes. I now see, when I login to MyDSTV, that instead of a credit somehow my outstanding amount has doubled. This is F**king ridiculous. DSTV - there are many other options nowadays, so sort yuor nonsense out.