DSTV Multichoice in breach of contract

I had the DSTV Compact package at R399pm. In Dec I took advantage of the Black Friday deal to upgrade my dish and my old PVR to the new explora at a special price of R499. For an additional R99, I took the movie option. My new total was expected to be and confirmed by DSTV to be R598. I was debited over R900 and on enquiry I was told this will be my new monthly debit amount. I was told I had 2 DSTV subscriptions on my name. This was a mistake. Instead of upgrading my contract, they added on another one. I asked for the one to be cancelled, as DSTV made a mistake. They told me my new price would be R499 subscription + R178 for the DSTV payment plan +R99 for the movies channel + an access fee of R100. My new total would be almost R800pm. I told the consultant this is wrong and that I had a verbal contract with DSTV for R598pm. I told him he can listen to the recordings. The black Friday deal was R499 all inclusive with the R99 add on my new deal should be R598. Multichoice made a mistake and is costing me money. Multichoice refuse to correct their mistake. They are in breach of contract and this is *******. As I verbally agreed for my account to be debited to the amount of R598 and they are debiting more, this is theft and is also *******. There refusal to fix there mistake to assist me to resolve the matter is unprofessional, morale reprehensible and completely *******. I have phoned Multichoice multiple times, however they refuse to assist me.