Refusal to refund my R400

I am so disappointed in the service i received, when signing up to Discovery I received a call advertising the Vitality program and that I have 4 months free to use this and to cancel within the 4th month should I not want to use it. I done just that and still got billed within the 4th month ??? And now I have been told the matter has been with the escalations team and I phoned twice and have been promised a call back and have not received it ?? Just when on chat and they stated my cancellation has been processed for the 31st of August?? Just so they can bill me AGAIN when i do not want it. I had high expectations for Discovery and I was going to insure my car with them but if they cannot even give me my R400 back i’d rather not.