Unfair Treatment

I skipped an exam last semester and app**** for aegrotat.Paid full amount (+/-R260) for the aegrotat.This semester I requested a quote for the subjects that I registered and gave that to my employer. The employer paid full amount as per the quote. We started receiving results a few days ago but this morning when I checked my results I got a message that says I owe R360 and could not view my results anymore. Went to UNISA to enquire and I am it's because of the aegrotat.