WRONG OUT OF BUNDLE BILL. NO REFUND REQ: ***

I upgraded my cellphone contract with MTN on 3rd August 2015 after my previous contract ended. My new phone had a limiter activated in store at Killarney, Johannesburg by Lindani Moyo, who acknowledges that I have been incorrectly billed for over R1740 for August - instead of R619 as per my contract. I was told that the bill could only be queried once I got my statement mid August. It's now the 1st September and I am still getting no response from MTN's Accounts Department in spite of Lindani emailing Jonathan Scullard about this query back and forth. I am owed over ?R1100.00 by MTN and I want that money back today before I report this to the Ombudsman as it has completely inconvenienced me. How can it take so long to sort out this query when the fault was completely the MTN Network's because of a technical fault on their side?