Why am I being called to pay a cancelled contract?????

<p>So I had two contracts with cell C. Called them on the 29th of November last year to ask them what I needed to do in order to cancel the contracts. They told me I had to pay 2 certain amounts, into a Nedbank Account and then reference the cellphone numbers on the deposit slip, then fax it. Which I did. I called them the next day and they confirmed that the money was received and that they'd be cancelling the contract and moving my numbers to prepaid, which they did. Now I'm shocked to receive a call this morning from someone at Cell C, who tells me that I need to pay R649, 50, which she says is my monthly bill for December. I don't understand, because one, that's the amount I paid to cancel one of my contracts back in November 2016, and my monthly bill for both contracts was R264, now I'm told I'm being billed more than twice that amount for one account??? Where is this bill coming from? Now she's telling me about being handed over to lawyers if I don't pay this R649, 50???</p> <p>I will not be paying for monies I don't understand. If there is any cancellation fees I should have been notified of that when I initially asked for the amount you want me to pay in order to cancel the contract, heck I would have paid for it when I paid all outstanding amounts last year. I never missed any payment y'all, and when I was cancelling the contract I did everything as I was told, even after cancelling my contract I remain a loyal cell C customer. Now Why am I being treated like this? No man!!!! </p>