Missing payment , Bad customer service and giving client wrong information when selling

Good day. I was contacted by on air agent, claiming to me he was calling me from multichoice, adviced me to upgrade , giving me a wrong premium that I'll pay, I was advice they will only debit R90 a month, but after they debited R139 , when I called and complain, they said I ddnt hear correctly, then I told them to cancel the contract and take their decoder, and they told me is not possible since the decoder is opened

I therefore reversed 2 debit orders , then letter I decided to pay it and continue with the contract since is affecting me nagatively on it. Their agent called me, we arranged and eft payment, I made a payment of R419 on the 20th of February 2019,which covered 2 months, I then continued paying my monthly premiums. Their agents keep on calling me I owe 2 months premiums, I told them I paid, then they asked me to send proof of payment, Ive been doing that since February till now with no help, Ive send proof of payment of their whatsapp, on their email,I called them dozen times with no help, and now my problem is all this is affecting me nagatively on ITC, I regret being in contract with them, Thier service sucks , and there is too many people complaining about them, I feel like I was forced to be in a trap to take this contract... Iam not treated fairly as a customer . please assist hello Peter