Extremely Simple Investigation being Prolonged

My initial date of complaint to the ombudsman was on the 9th August 2017. On the 14th August UNISA responded insisting that I wrote specific examinations. Initially I got a quick response from the university after my complaint to the ombudsman but once I rep**** to their feedback disputing that I didn't sit for any examinations that they charged me for, they have since not responded satisfactory. UNISA keep responding asking someone else to sort it out and get back to me but that has never happened to date. The latest response of the university asking someone to "urgently intervene" was on the 6th October and almost 4 weeks later I'm yet to get any closure from this. UNISA charged and handed me over to credit bureau for exams that I didn't do. It's very simple, if I wrote the examinations under dispute then I would have followed the university's procedure of completing and signing the attendance document. So where's this document that I completed and signed? Which examination centre did I write these examinations at? If this document was signed by somebody else, with the intention of making it seem as if I signed it, then that's ***** which is a more serious case. Either way, UNISA is owing me money and they are taking their time to conclude an extremely simple investigation. If tables were turned and I was owing them money then they'd quickly hand me over to the credit bureau for blacklisting.