MTN Worst service!!!

I have a contract with MTN. it was due for renewal and a consultant by the name of Rashena Moodley called me. She told me i was due for my upgrade so I asked if I could keep the contract the same as it is currently, that being unlimited phones calls and SMS's and 3G of data monthly. she said it is not a problem, so I need a new device, which i accepted. The new upgrade with my device would cost me a total of R1169 per month... perfect. My bill for December was R2012!!!! I called MTN and I was informed that I have had to pay for the old contract and the new one as Reshina activated my new contract before the old one ended. I have asked for the phone recording as Reshena did not inform me that if I renewed the contract now I would be charged double, obviously I would have waited. I have asked for her to contact me as well as her manager to contact me and surprise, surprise, no one has called back. I also spoke to a guy in customer care named Siphesihle Ngcobo and he was no help either. Absolutely disgusting service from them and I will be taking this to ICASA.