What customer service?

What customer service you get from cell c I logged a a complaint weeks ago about my upgrade that I cancelled but now am still being billed and when I phone in to solve the problem the say they will out it on the system for the right department to investigate its almost two months how does it take to investigate that a client has cancelled and hasn't used the device and returned it with in the 7 days. But are very quick to send messages that payment needs to be done and further steps will be taking like ***?