CANCELLATION OF CONTACT - NO PRORATA - DAYLIGHT *******

I am extremely disappointed and disgusted. I have been with cell c for years. I am cancelling my contract, 20 working days before it ends (as per terms and conditions) So on the date that it is cancelled, which will only be 6 days of the month, the last payment that will be the end of December, and i am still going to be charged the FULL MONTHS charges, yet, i do not receive the service. I must USE IT UP as the woman says to me!!!! So, basically, my money is being ******, as i have given the relevant amount of time to cancel. When you open a new contract, they can then charge you pro-rata accordingly, based on the usage when the contract is taken out!!! Why exactly is this not happening when you cancel and account. Its a really good way to make you want to change networks with this nonsense.