******** deductions for Packet switched Data Calls

I upgraded my My Choice Top 100 in February this year to go from Samsung to Iphone. Without informing me, the consultant upgraded me to an unlimited My Choice package. This means that my account just runs up not informing me about additional charges. This was NEVER explained to me. My fixed contact for the past 2 years were around R640 per month. With this *********** adjustment, MTN deducted the following amounts: March R959.79, April R1 479.11, May R2 862.42 and June R2 218 (expected). I am really so angry about this, especially going into debt for this. I launched a query 6 times to the customer care email starting on 24th April asking about the overcharge. They came back to me TODAY (18 June 2015) telling me I must sort it out with Tygervalley MTN in my own time. Seriously?!