Pathetic Service

Cell C Is a **** first and foremost?I signed a contract to windows and they told me that my contract will end at a certain date.I waited until that time and I called in and canceled my conduct.Once it was completed. Then on the other hand they Never stopped invoicing me regardless.... today they call me asking me for money, I informed I cancel, then they don't have records because they failed to do so, luckily there was a cancellation sms.... This is pathetic, should I have not this info, they would have charged me!!!!!!!!!