Billing incorrect - no response from any MTN branc

I went to Egypt for 8 days and had roaming on my phone. I made no telephone calls and sent 5 SMS's. Then I was told when I returned I had a R3000 bill after speaking to the Call Centre operater. Two days later the bill had gone to R4200. I managed to get the call centre to deactivate my sim card. I also sent an email reporting the ***** problem. After a number of calls I was told they needed the itemized bill which would be sent to me. After another day I tried phoning to have a message telling me that the call centre was closed. For three weeks I tried the call centre and got the same message, needless to say MTN debited me R4200+-. My account had a R1000 limit on it so how is it possible that MTN allowed this to happen. I have heard a number of people who have had ridiculous bills as well. What is happening to MTN. Where does a person go from here? <br>