Very bad service

I have been struggling for a year to get help from mtn I talk to so many people at customer care and to the legal department nobody help everyone just pass me along to the next person they say that I owe them money from 2011 and the more I tell them that in 2011 I was still in school and 2015 the less they listen I got my first contact phone in 6 February 2017it was a iPhone 7 the lady that helped me is Julia radebe today I went to the sasolburg branch and they say it doesn't even show on the system that I have an iPhone 7 how is it possible that you don't even have the right details on your system why can nobody help me what does it help u have a customer care line if they can't help you can anyone help me resolve this problem how much longer do I have to struggle my contract number is ********** but my self phone number is ********** 295if u can help me please call me