Cancelled account still being billed

I recently discovered on my Vodacom statement that I was being billed for an account that should not have been activated at all. The account was activated on the 20/11/14. The device had been returned before the contract was activated but I am also still being charged for the device despite Vodacom having confirmed that the device was returned. I contacted the Cancellations department on 04/04/16 to request that this contract be terminated and my charges reversed asap which I was informed was initiated. The gentleman that assisted also made a note that the contract should not have been activated. I also reversed my month's payment subscription until the matter could be cleared up. I have consequently called several times since in the past week to verify whether the contract has been cancelled and been informed that it has. However, I have received a statement that indicates otherwise. I also have been told by the accounts department that I will not be refunded for the ***** up by Vodacom because the cancellation is after the 14 day period. Really? This was your mistake. Until this issue is resolved, I will be reversing all future debit orders.