Incorrect billing and no feedback.

I renewed my cellphone contract to the agreed amount R525 PM. This changed to R1008.00 without my knowledge or any communication and my bank account will be debited in a few days. I have called in queried this 2 weeks ago, disputed the contract bill and still waiting for feedback. I was told that my contract agreement is R699 which is not true, but my bill shows payment due R1008. Please go back to the phone call conversation and listen how the lady/consultant told me R525 PM and that is what I agreed to. Please stop changing packages on behalf of clients and just debit bank accounts as you please. Adjust my contract to R525 PM as agreed on a recorded phone conversation and leave it alone for the 24months don't go fiddle in things I did not ask for. A response will be nice with a resolution - Thank you!!!!