Cell c dont value its clients

Once again cell c refuses to acknowledge that they are wrong. I have been trying to cancel a contract long and they refuse to help. My contract ended in july last year and when i called to cancel i was told to go to a top up line month to month at 30 a line and the lady said its month to month so cancel anytime. When i call to cancel they said that they did it and i get billed again so the lady did a listen in to the call recording and said ahe was wrong so she will cancel and give me 2 months free service. Next month they debit again. Now they debit me 280 more and aay the line was a special and the promo is over ao i have to pay 280 which is 120 a line for something i dont need. I still got a cell c data line which im happy about. I have reversed the debit and will continue to do until im devited the amount i agreed upon. This is expected from small companies but not 1 as big as cell c. Now they send me this sms"Good day Please note that the charges on the account on your account are valid as you were on the month to month saver plan when you request for a cancelation on those contract we charge the full subscription fee there is no discount on. Good luck getting the funds from me until you have it fixed up. Thank you nedbank for letting me reverse these debits for just 5 rand from there app.