Vodacom contract cancelation nightmare

I've called Vodacom over 7 times trying to cancel a contract with them. Each time I am told that my contract is on a different system that the agent can not access and will escalate the issue to a senior who will call me back as soon as possible. Since June, the so called senior has not called me back once and therfore my contract has still not been cancelled. When I go to the stores near me, they tell me that they are franchises and can't help me cancel my contract. This is pathetic service from Vodacom. Why isn't it as easy to cancel a contrat with you as it is taking one out? I am highly annoyed with this network, as soon as this is sorted I am moving.