Vodacom contract cancellation

Vodacom does not want to cancel my contract, told them in December to cancel it they did not,Jan and Feb they debited,I called them in Feb after several calls I finally managed to speak to a consultant who said they will cancel my contract I will receive an email,waited for that email until today, just got a call from them today a month later asking if I want an upgrade since my contract is coming to an end meaning they did not cancel it,I’m fed up with Vodacom and just when I try to talk to the guy he hangs up,I’m so fed up!