Unhelpful staff

So last weekend I paid a settlement ammont for my tablets contract. When I have called the call center to ensire that the contract is cancled and paid up, as I have also sent in the paperwork, I get told I cannot be helped. I get directed to a second call center and recieve the info that I must call the first call center again I no longer want to be a Vodacom customer as I have had many issues over my contract period, even though I pay ahead of time.