Useless service and difficult cancelations

Vodacom and their consultants are useless. All I want to do is cancel my contract which I am wanting to end since March this year and all their consultants do is tell you they cannot help you and give a useless number that always says the contract ends a later stage and my contract already expired and the lines are forever busy for one to get through to a consultant. I was called to be put on a new package as the current package was old which would cost me R208 but now I see my next bill will be R396. Why is this? I haven't gone for an upgrade as I am no longer interested in a contract. All I want is to end the contract but vodacom makes it so difficult for this to be done