unfair treatment

contract was about to expire and was consultant and I indicated am going to cancel contract and use as prepaid. Instead ***** occurred in my account and I send documents and request again for contract to be cancelled but it was never cancelled. Vodacom billed my account and I called for cancellation but they never did as I was moved from pillar to post and customer care saying Vodacom legal was supposed to inform, to this day account is handed to their subscriber collection and they going to hand me to debt collection