they will not cancel my account

I have been trying to cancel since early Nov. I am calling just about every day. They take my time by demanding all my details and then eventually passing my call to the cancellation department. I then have to give the entire story again. Then they put me on hold or cut me off. I have already been debited for R600 during this period. I was first told I would be refunded and then I got a string of rude messages that seem to say I will not be refunded. I have also now been told that my service is no longer active, yet I've had to pay for a full two months of no service. There is still no written confirmation of my cancellation. I've had enough of this.