MTN Uncapped - being charged for DATA

I have three contracts with MTN, all for data, on the following numbers:<br> <br> *** - taken out July 2012 - uncapped<br> <br> *** - taken out July / August 2012 - also uncapped.<br> <br> *** - taken out June 2013 - Capped. Once data runs out the stick is no longer useable untill the next month.<br> <br> MTN have charged me almost R2,000.00 (two thousand Rand) for data on these accounts for the period October - November 2014.<br> <br> I have made several calls to the call centre without a resolution. I called their legal department on 19/2/2015 and spoke to one Luciano. He promised me an answer within 3-7 working days. To date I am still waiting (reference for call of 19/02/2015 is : ***).<br> <br> Can anybody at MTN please explain how its possible to accumulate data charges on accounts which are uncapped ? Or for that matter on a capped account.<br> <br> I have been sent threatening letters and am not happy with the situation.