Rediculas high account for a R100 contract

I am now tired of trying to get an answer out of MTN of what is happening to my son phone contract (Mychoice 50 with 100MB data)<br> <br> I have started in July asking for a reason why there was a Packet Switched data calls on this contract - no reply. When I did got a reply they said someone phoned in and change it and then that it was done on the phone. I went to my sons phone - looked through his log could not find evidence that he phoned. His credit limit on his phone was R1.00. He did not even know how I got there. .<br> <br> I paid end of August R1994 for my account that is normally R650. When I got my accounts again it still did not change - it is actually higher than what it was. Still no comments of info from MTN until now.<br> <br> I cannot pay this amounts and it is not my son that is doing this. His phone was this month under my supervision. <br> <br> I do not know what is going on but it feels to me that someone is enjoying him/herself at my expense and it need to stop.<br>