DISGUSTING *********** SERVICE FROM MTN

I am TOTALLY DISGUSTED BY THE SERVICE I AM RECEIVING FROM MTN SPRINGS MALL! To have been debited twice in a period of 10 days... Worst part is the people there do not even understand the concept of a pro rata. I took my modem on the 8th May.. As expected no amount was deducted for that month. On the 20th and amount of R512. 26 gets deducted off my account & I understand it that R183 is for month of May then the R329 the month of June. To my surprise another R329 gets deducted on the 30th. I neeeeeed a competent mtn person who knows what their work is about to contact me and help me fix this because the service I'm receiving from the people at the store stinks.