MTN Unwilling to Resolve Account Query

I have had a contract with MTN since 1995. So far I have had only minor complaints about the service I received from the service provider. During February 2015 I upgraded my data bundle to an 24 mth My MTNChoice 2GB - then my problems started! In April I received a statement for R1201.78 + TAX and again in June for R961.03 + TAX for packet switched data calls.<br> When I received the first statement, I went to the MTN store in North Park Pretoria North and filed a query, and also several times thereafter, but got NO response. I also requested intemised billing statements as from February till July 2015, but to no avail.<br> Since I first got the data contract in 2013, I never exhausted all my data in a month!<br> If I'm really responsible for the data used, I'd be willing to pay for it after I made arrangements with them.<br> In the meantime my service has been suspended and MTN expects me to continue paying even though no service is being rendered. Attempts to resolve this problem with MTN has been utterly unsuccessful.