DStv - My account

Good day
I have 2 decoders of which they are both compact, on the past my premiums was R958 a moth but in the past 3 months I have been charged more on the first month they charged me 1900 when i called the call center asking them about the amount they charged me they told me that they added the 3 decoder which was premium by mistake second month they still charged me around 1400 when i went to their service center to ask again why I am paying so much money they told me that i have added Netflix on my account of which i did not do so they asked my email so that they will check that i registered with Netflix i gave them and it appears that i did not register with Netflix even if they put my contact no still it was not showing that i got an account with Netflix now it's the third time still they charged me around 1400 and i am sick and tired of me every month i am complaining for one thing and i don't get any help from thaier call center please help me