Account Handover

MTN has assisgned my account to external collectors without my knowledge and the balance brought forward to me is R5976.79 by Shapiro Shaik Defries and Associates ***. When i phone MTN to enquire why they handed over my account without consulting me first they say they assumed since I did not pay for the past 4-5 months they had no assurance that i was going to pay. They also stated that they've sent me sms's to my number of which is not use anymore since the laptop was ******.They didnot make any efforts to contact me or send me statements for the past 5 months.<br> <br> MTN Legal department stated that my account was handed over to the attorneys with the balance of about R2500.00 in June 2015 and i asked where is R5976.79 originate from since i was only contacted the attorneys today(11/08/2015) they couldn't answer. I requested the statement and they couldn't provide it too. <br> <br> I need to know how R2500.00 can rise to R5976.79 in just 2 months? and Why i was not contact by MTN for payment arrangement?