crazy bill and no reply

I have been a loyal supporter of Vodacom for many years. in September I upgraded my contract to find myself landing a bill of R4580 rand. I'm furious they are charging me with data I apparently used. firstry I specifically told the lady the upgraded my contract to block me once my gig is finished, secondly they are charging me for apps I never used and thirdly they were supped to get back to me on Monday, I'm still waiting. I'm so disgusted how do they Expect me to feed my family. who has that kind of money for a phone. I don't care what they do with the charges but if it is not reversed I will kindly move my, my husband and my kids accounts over from Vodacom to another service provider.