Incosistence in Marking

Im so so disappointed by Mancosa,there is no consistance whatsoever. I resubmitted 2 assesments (Taxation 3A and Financial accountinf 3A) when they came back questions i had got correctly were now marked wrong and i dont understand how because i was supposed to improve on the parts i fot wrong. MANCOSA please fix because when i phined for the Fin Acc i was told not to worry as i still meet sub minimum mark to pass,then the same thing happened to Taxation??please make it make sense???