Questionable bill. Poor service

My original bill was around R480 since late 2014. Last month it was R511. This month it is R533. I queried the bill and was told I was being charged for a recurring International bundle. However, I always buy airtime and convert to bundles when I want to call outside South Africa hence was billed twice. I called the Call centre and a complaint was logged. I was told I would be refunded and that the international bundle would be cancelled. This has not happened. I called again and was given the same promise. I then emailed Customer care and got an automatic reply that my issue would be resolved...nothing has been done. To make matters worse, I always have low or no network reception and people tell me my number is always not reachable. I am tired of Mtn services and I feel I am being ******. Please stop the recurring international bundle as I prefer getting it as need arises. My bill keeps escalating and I don't understand why. Can I have the original bill please!!!!!