Added data on my account and forced me to pay for

Good Day<br> <br> I called 1 night in to MTN call center , to order a 1 gig data the call center agent loaded 2 gigs , I informed him about the error he then loaded the 1 gig , but never removed the 2 gig I call like 10 times into the call center to correct the error they assured me that it was removed but when I went to pay my account on my account I had to pay : R160 for a 1 gig and R260 for a 2 gig , with in total is R420.00 , they do not want communicate with me .<br> <br> I would like the matter to be Cleared please that's all I want