Trying to find out why data so high

Reported this matter in July 2015.First response I had from MTN was in September of 2015 from Alice vd Merwe. Further on nothing more happened. Alice promised on 08/09/2015 at 11h38 that she will get it to me within 10 days. Up to today 01/03/2016 nothing as yet. Her reference number was REQ:*** .After this I followed her up numerous times but with no luck. I see now that she reads my emails but doesn't even respond to them. On 01/03/2016 had another debit for R 11000-00 through my account but I don't even have the first answer as yet. This is really ,really of the worst service I ever had. Looks like big giants like MTN does not have to respond to any customer queries. Again this is really the WORST service I have ever experienced in South Africa. WOULD REALLY JUST LIKE TO HAVE ANSWERS.SHOCKED IN HOW THIS WAS HANDLED.In July 2016 this will be going on for one year.