Lead into a contract under false pretenses

I currently have a contract with Vodacom for a router and data bundle that I am paying R200.74 per month. On the 31st of January I received a call from a Vodacom, the person whom was assisting me stated that Vodacom is re-looking there data bundles and because I am a long term client they would like to offer me the same package just with a cheaper fee paying only R169 per month. I informed the agent that I already have 3 contract with MTN and 1 with Vodacom and I can not afford another contract apart from the ones I already had. She ensured me that I will only have 1 vodacom contract and nothing changed except for the payment this was also confirmed by her "manager" several times. On the 1ste of Feb I received a new sim card and had to call vodacom to activate this sim, this was very strange to me thus I asked the person whom assisted to activate the sim if they are sure I only have one contract. This is when the agent informed me that there is 2 contract and not 1, I explain the situation and he informed me that he would escalate the matter to stop this contract. He also said that it will take 7 to 14 days to stop the contract, after the 07th of Feb I called again to confirm whether the contract was stopped and they once again promised that Vodacom has stopped this contract #incident 1- ********** ********** . Today 29th of March Vodacom deducted R467.39 how is this possible that I don't just pay my normal installment but I pay for a contract that was activated under false pretenses and pay an additional R100 for what? The consumer protection act clearly states that I have a cooling-off period of 5days which I did log a call as soon as I was aware of the second contract, please note "All Your Calls are Recorded" so please use this as reference. Vodacom must also please inform me when I used the data as I was informed that I should destroy the sim card as the contract is cancelled??? I would love to hear how they will be explaining this???