FRUSTRATED CLIENT

My name is Rebotile Mashale and im a customer of multichoice ,as a client i feel that i have been treated unfairly .I subscribed to their their services on the 29th of May 2015 and later upgraded my option to DStv compact and since then i've been receiving messages about outstanding amounts ,first it was R35,70 for pro-rata ,then R42,20 for changing my payment date from the 29th to the 2nd of every month ,both of which were not explained to me. I have called multichoice and they always have some excuse for the amount and apologize for not telling me about the amount at the time of the transaction ,but i'm fed up i can't always be paying for the things that i didn't plan for n this is inconveniencing me and i can't live like this anymore, not knowing what amount is going to pop out next because i always pay for my plan and later receive messages about outstanding amounts