DSTV constantly overcharges me!! It's time to switch

It's starting to feel like some kind of conspiracy against me for Dstv to keep overcharging me even though I am on price lock premium. To this day, I'm waiting for my account to be credited with an amount that I was overcharged with in September. And now I've just viewed your app only to see that alas! Dstv has done it again! I'm on the R899 price lock and only rented one movie for R35 but amount due shows R1269.33

I called your customer centre only to be told that I have an Indian bouquet and another active decoder of which I'm not aware of. Now sending an email to you would be pointless because I have countless emails dating back to September that were unanswered. Your call centre agent could only tell me that the issue will be escalated. Dare i short pay you, you will immediately suspend my services but here you are dstv, comfortably overcharging me and dragging your feet to credit me. As it seems, you're incapable of keeping to your contractual obligations therefore I do not see the need for this contract to exist. But because you are ********, you will tell me to pay some kind of cancellation fee. The inconvenience caused by your lack of customer service leaves a bitter taste in my mouth. Again, I will wait for your response. I've made contact via social media, email and phone calls. Humour me and rectify your mistakes.