Vodacom fibre cancellation issue

I call to cancell my vodacom fibre and the guys kept foing on to give me a beter deal and was not instrested but he said the cancellation is logged.I saw the next month they were still deducting money for the service.I called again and the guy went through everything and said that it was not logged but he listened to the conversation recorded that did cancell, he said he wil log it and I will be refunded.I saw that they still did not cancell the service.I called again and now they said I never called to cancell my service but they can offer me a beyter deal.How do they expect the I want to stay at a service provider that cant even do what I ask