Not refunding Airtime

I upgraded my cellphone contract in the beginning of August 2015 and I was not informed that I would lose all my current airtime when I upgraded my cellphone. Due to receiving inadequate information I lost R2,138.27 worth of airtime. If I had received the correct information, I would not have upgraded my cellphone. I have been trying since the end of August 2015 to get a refund for the airtime lost, but with no access.<br> <br> I have been dealing with Nokuthula Ntozake from the MTN Greenstone store. She doe not reply to my emails nor does she phone and give me updates. <br> <br> This services is shocking and unacceptable.<br>