disconnected services while more than due amount p

Mtn has disconnected my services for Internet usage for an amount payable of R119 incl vat I made a payment of R1250 on my account in the same period and the balance owed to myself by Mtn is in the tune of R1131 I had not used the data card before yesterday afternoon and when I tried to log on this morning to use it I was disconnected I have 2G allow every period and I have not used it in the last 6 months as I connect to server. Our server has been down all w-end and when the only time I need to use my bundle it's disconnected. What exactly am I paying for, this is worse than Nashua Mobile why they transferred us to MTN is beyond me. On top of that I have been calling all morning and being ignored and told systems are down. MTN systems are always down. When you need to pay they are down just so they can take more money from you and claim you never paid. Is there anything Mtn does right? They are such Bad serProvider