No answers about over billing

I was overcharged in May for a 2GB ad-hoc that I didn't purchase. I submitted a query on MTN Active in the beginning of June. I then visited a store which informed me MTN was on strike and they couldn't help me with my query. I went back in store (Clearwater Mall) again in the middle of June and processed another query with them. I have still not heard anything back and would like this billing issue sorted and my money back. I have tried calling and tweeting to no avail. I can not believe this terrible customer service. It has almost been two months trying to get some one to fix an MTN error.<br> Please help?!