Unhappy customer

I no longer trust this company. I am on pricelock from last year and my contract agreement was to pay R550 every month and last month they deducted R650 and I questioned that and the answer I got was that my contract was coming to an end on the 26 Of November so I had to settle a decoder and I accepted that even though I dint understand the explanation. This month I took a new contract of which I was told that I am going to pay R439 and I was happy until yesterday when I received a message that they will be deducting R650 again. This is not right. Multichoice is not honest and their contracts have loopholes that they hide for their customers. I will not pay something that I did not agree with