Disgruntled customer..

On the 5th June I took a cell c data contract, the sales person told me that if I'm taking a data only contract and will be using my device I can cancel the contract anytime and also assured me that there is reception in my area. A day after I battled to connect with no luck, I called the offices and I was advised to roam which I was not comfortable with and as a result I ended up cancelling the contract. Khulani Ngwenya at cancellation department assisted me with the cancellation process and even told me that the monies are going to be debited from my account month end of July but I should just call the office for a refund. Month end indeed the money was debited from my account, and I reversed it as I didn't want the hassles of calling the offices for a refund. On the 15th Aug the Money was once more debited and I reversed it. I called them on the 20th Aug, spoke to Khutso and Irene to find out why are they still deducting money from my account and I was told that the account was not cancelled and they will get back to me once when they have spoken to Khulani which they never did. On the 28 Aug I was called by Robert who was very rude towards me and told me that I must pay the monies because I've taken their simcard and opened it, therefore I must pay. And I was told that the account cannot be cancelled due to outstanding amount. But what I want to know is why should I pay if I never got to use the data and why should the contract not be cancelled if they can clearly see that its not my fault that my account was not closed... Please help