Month-to-Month contract cancellation woes

I have 2 contracts with Cell C, the voice contract on Month-to-Month and a data contract that expired in the past month. The shop assistants refereed me for the cancellation to their call center (why??) and after a long hold I was told that both these contracts will only be cancelled in 30 days time (the cancellation period as stated in my contract apparently) and the voice portion will only then be transferred to prepaid.<br> <br> What is the use of a month-to-month contract if you cannot cancel it with immediate effect (not even mentioning a contract already expired)? Now it will continue till the 5th of the next month, meaning I get billed twice from the time of cancellation. I dont mind paying for the month I am in, that is given. But withholding the voice nr's switch to pre-paid needed for a number-port for the full 30 days is unreasonable. Charge the outstanding fees and let me go!