MTN SUSPEND LINE (PAID) DUE TO OTHER LINE ERROR

I took out a cellphone contract for my son in July 2015. It was a My Choice 25 Top up. On the day I took the contract out I told Tshepo that I want a Top Up contract because I need the phone to stop at the amount of R25 and then we would Top up again. I specifically told him that I do not like surprises. In November I received a bill of R6865.40 for this line. I reported it and they said that I should have put up a limit. I took it up with Tshepo and he said it was a mistake because it was a Top up contract and not an open line. Myself an Tshepo have been trying since then to resolve the issue with MTN. I went to Tshepo in December and ask him what I really need to pay (without the mistake), he informed me and I paid it on EFT. On Tuesday they suspended ALL MY LINES because I did not pay the full outstanding amount.<br> <br> I feel that this is not right. By all means suspend the line that has the issue but WHY SUSPEND ALL MY OTHER LINES WHICH ARE FULLY PAID?<br> <br> Please assist me to get the other line suspension cancelled while they resolve the query reported on 26 November (ref ***) and 3 December (Ref ***). Tshepo Moeng number is *** or *** (private)