Mtn has no idea what clients are billed for

On the 23rd November I received an sms stating that my order is being process, as I have not ordered anything from mtn I called to enquire and was informed that my line had been suspended due to an outstanding amount from July. I further enquired what this amount was for i.e a subscription, admin fee or short payment on my installment. I spoke to 3 agents on the day where is was informed that not one of them could see where the issue is and that my account should indeed be in credit as my contract installment is R390 and I have been paying R400 every month. I was informed just to pay the amount to clear my account even though no one could furnish me with an explanation as to what this amount was for. I then requested to speak to a manager and was transfered to a Jothika Abbana who I was informed was a manager but just found out that I was **** to and she is an agent who has responded twice between then and now to my daily emails with a standard response that they are working on my issue. I then reached out to the the mtn facebook chat on he 11th December requesting assistance as Jothika was ignoring my emails where I was assisted by an agent named MM who informed me that they will send me statements since July for me to try to find the issue. Again another agent who could not inform me what the payment was for. I asked MM in numerous messages to please check what this amount was for where my messages then got ignored. My line again got suspended on 14th with the same issue where I called 2 agents due to the first one who I had spoken to around 16:00 dropped my call. The 2nd agent informed me that I should be a month in advance as in July the credits available on my account was used as an installment and was R85 short for the complete installment. When I informed her that I also made payment in July for R400 she too could not inform me where the issue is. This is the most pathetic service imaginable, how can not one person in mtn find out what this amount is for and how this entire mess happened and how nobody has contacted me regarding this since July and we are now in December. This is unacceptable as my account is paid timeously and in access of the contract amount.