Vodacom refuses to cancel contract

I have been trying to cancel a month-to-month contract with Vodacom for weeks. They promise to cancel and send confirmation but it never happens. when you call them the person you speak to is never the correct person and can never assist. Promises is made that somebody will call back that never happens. I would like to know much money they stand to make if they delay cancellations by weeks for each person? Cancel my contract as requested weeks ago! <br> Also, please furnish me with proof (as requested weeks ago) that I gave permission for my personal data to sold by Vodacom and that Vodacom my market to me. While looking for the proof - stop selling my personal data and tell the people you already sold it to without my consent to stop calling me.