Overcharging my account for years!!! *******

On August 2014 DSTV launched their new HD decoders at a price of R499. A fair deal and great to watch sports in HD quality. Our package at the time was DSTV Compact + South Indian + Extra view. Paying around R540 per month. I called the call centre to swap over from our old decoder to the new HD decoder. Last month I called in to cancel the South Indian package, When I asked the agent what is my current billing she told me it was around nine hundred rand!!! Shocking, My old decoder was not swapped instead back in Aug 2014 your *********** staff just added the new HD decoder as an additional decoder and didn't cancel the old one. We only have ONE dish how can we have THREE decoders active on one dish!!! I will not lose out on all of the extra cash that was debited of my account. I want a refund for all these months that I was overcharged! <br> <br> I have been a loyal customer for years and even trusted DSTV with a debit order going off my account without a fail. Feeling disgusted being ****** for all of that cash.