Extra money debited after I subscribed for price lock.

I was paying compact bouquet and around R80 for extra view on 2 normal HD decoders. I therefore subscribed to Price lock and I asked extra view to be installed which I believe there is no charge for it. I now have 1 Explorer hooked up to 1 HD decoder as extra view. My price lock amount is R540 or R550. My premium before price lock was up to date when I opted for price lock. Immediately after price lock I was then debited over R1000. I called in and one agent advised me that yes I was over charged and the best thing to do is to reverse the funds at my bank and make a manual deposit of R540 or R550. I did as he said even though it was a hassle for me as my bank branch is far. I logged in to chat thing to request for account number so I can do EFT as I am at work that whole week which were successful. This month I was again charged over R700 and I am really ****ed. No one can explain why and the agent I spoken to yesterday told me that my last month premium went unpaid and I have proof of manual payment and hopefully chat transcript when I requested for account details unless the agent gave me her own account details. Multichoice can't me and still they are telling me that I am on arrears. I do not agree to the whole system and I want my change from the R740 + that was debited. I know DSTV run on prepaid and no extra must be charged.