MTN is taking us for a ride

This whole problem started when my contract was transfered from Nashua mobile to MTN. Ever since then i have received really bad service to say the least. Im being billed for data that im not receiving. I call the callcentre and if i get through they say i will get creditted in the next months statement but that never happens. I was told that that this contract bills R0.02cents per second but when i compare the amount on the statement to the amount on the itemised billing statement it doensnt match. For Feb the itemised statement says R88.17 and the overall Feb statement says R174.32 for the same amount of calls. MTN is taking us for a ride and im going to place an official complaint with the NCC. There is no transperancy in their billing and this can not be legal.This contract allows me to also top up my own airtime so I loaded airtime for R150 last night and made calls of 34 minutes and 89 seconds and now my airtime balance is R20.00. I had data of about 80mb and that didnt change but my airtime is gone. This is daylight robery!!! I will not pay one more cent until all this is sorted!