VODACOM'S DISHONESTY AND BAD SERVICE

I have a two year contract with Vodacom ********** ending November2018 at an amount of R289.00. This contract is being paid to date. In June 2017 I received a call from SIN***SAHS of Mondeor Mobile who introduced himself as a subsidiary of Vodacom offering a special of R99.00 to the existing clients for two years which I took for my child who is in tertiary .Once delivered the amount changed to more than what was agreed on, I requested to cancel but was told that it should have been cancelled within 14 days though I received statement very late. I have called their call centres several times, went to their Midrand offices but was not assisted however I was given an e mail ********** I have e mailed twice but still no response from them. My initial Vodacom contract ********** is blocked though it is paid to date but I am unable to use it as it is linked to this disputed number of ********** 454 of R99.00.Please assist as I am paying for something that I am unable to use. I feel that my rights are violated as a consumer moreover I have honoured the initial contract that I have signed for. On the recorded call agreement I agreed on additional R99.00 not more, the consultant even called his manager to the phone to convince me that it will be R99.00 as I was explaining my financial situation.