poor service still

a couple of month back i wrote a review here regarding the poor service from vodacom after trying to cancel a contract . today it saddens me to write that after many many months of struggles Vodacom is still charging my account for contracts canceled with them .Numerous phone calls to vodacom later with no action what so ever its time to maybe withhold payment or something can somebody please give me some advise as to how i can get them to take action as promised