Lying, cheating and giving us false hope and exploitation

I have been a very faithful customer of DSTV, never skipped a payment. In July DSTV started calling about a free DSTV explora that they are giving me which I will pay less that what I am paying now (R809). To (R780). Until in October I decided to take their deal. But now I went to pay DSTV today and found out that I owe them double the amount that I normally pay (R1600) in total. I called and asked what happened to the deal, the consultant was rude and with a lady laughing at me while I was talking. She says she got a special deal, I quote. Please assist me because this is not the first time DSTV takes advantage of me. The other time they claimed I didn't pay them and cut of their services. I sent a lot of proof of payment to get my services back. This is bad business and I am not paying them double