Massive overcharge

About a month ago I was billed R3400 by mtn apparently for data charges. I reversed the debit order so I could investigate the situation. I followed the correct channels via phoning Mtn and the lady I spoke to promised me that my dispute would be escalated to their validation department and that they would then get back to me. At the bottom you will see that the have the time to respond to me via sms to tell me to pay them but they can't take the time to phone me to give me answers to my questions.<br> <br> Yello, overdue account warning. Please pay R 3491.93 to avoid service suspension. Make payment to ABSA Bank, account no. ***. Kind Regards, MTNSA