Incorrect billing

I am aware how telesales agents operate, they call you with a pitch all exciting and probably what you wanna hear, but when it comes to charges they are never professional enough to give you the correct charges. Mtn contract was sold to me, *** a month ago via telephone, I may not have recall much of the conversation but I vividly recall being told more than once that I am only going to pay R100 each month for a data contract. I recieved both sms and statement via email advising of R157? I do not like such costly surprises and what I detest the most is the run around you get when trying to get help via call centre, I am not happy as I feel stupid to think I heared correctly to the R100 speech but I am writing this review knowing precisely I heard right, R100 per month is what I agreed to. Please have someone to contact me via email ***.