MANCOSA frustrations

I got and invoice by MANCOSA with two modules that I have been credited for at the beginning of the year, and payed all the fees cash over R50000, now they say my account is in arrears because of those two modules, I reported this on June, no response since. Then today I request for my result and indicated that there is an error, whiles some students received their result after reporting such within an hour, I must wait till tomorrow because of their command structures, MANCOSA is inconsistent, mind you I waited on the line for 18 minutes.