Bad service!!

I am sooooo unhappy with Mtn every month my amount that is due differs and when trying to call them I only get a robot to talk to! I send an email asking they should call me and they wanted personal info that I am not willing to share that over an email I left my number! I have not since gotten every response or any thing. This is unexpected. They can either gibe me a number so I can talk to a person o4 phone me at least!!!!