Called looking for assistance regarding over billi

I called this morning because im expiriencing a serious problem whenever I use my mobile phone surfing the net instead of taking data it depletes my data also my airtime when I asked to Mpho to assist me she said the only thing I can do it to switch off my data meaning I must not access my emails nd stuff like that,im very angry as mtn has given me a very horrible service its been more than 3 months now my airtime just vanishes and there is nothing they are doing about it because its not their problem.Mtn I have been your client for more than 5 years now shat do I get a thank you like this????I want my aortime please