JUST GETS WORSE AND WORSE

i have this contract since november 2014 and every month i get charged 100.00 extra to my bill and when i call in all i get told is there is some lifestyle subscription on my account ( which i def did not apply for ) and i always get billed wrong never once did i just pay the correct installment i was always over charged R371 is what i am suppose to pay but i get billed R465.50 why ? i literally call in every month regarding this and nobody does nothing all they say is they going to credit me back but on the next month they just take the same or more money again DAMN... this is my 9th months on this contract and i cant say not one month i have a pleasant installment go through ... i have so much issues with this handset the first time i got it i sent it back and they sent me a refurbished phone and i was still within my dsr period then the phone was missing by them for 3 months i still paid my installments with no phone and they nli credited me 900 back. im so angry and really not happy i want to cancel this contract and just close my account aswell never ever had i had such a issue with another cellular company SUCH A DISGRACE