Appalling customer service and bad advertising

I'm or as a DSTV subscriber and about two months ago I received a mail from your company that of I upgrade my account from compact to premium I will pay R599. I did just that and I was charged R949. I raised the issued numerous for mistake to be rectified but nobody seems to care. I have spent hundreds and hundreds of rand contacting the call center and the supervisors about this issue and all I get is empty promises, I have even contacted hello Peter but your employees weren't phased by that either. This is my second message in hello Peter. Last month I asked to be downgraded and that's still not done either so they keep wanting me to pay money I can't afford.