Honesty is no longer a virtue?

I have been precluded from 'Korean 1' because I have some prior knowledge of the language. I thought honesty is the best policy so I decided to declare that I know some Korean but definitely not everything or majority of the syllabus that 'Korean 1' will be going through. Upon hearing that I have some prior knowledge, the lecturer told me to leave the room as I am not allowed to take the module. Can you imagine how shock I was? I crawled out of bed at 5am, made my way to school at 6am and reached school at 8am for the Korean lecture to be told that I can't take this module.

In the first place, the website that introduces the module did not state that it is strictly for complete beginners. I don't think it is my fault at all for choosing some module that I have interest and slight knowledge about. I feel very upset over this and couldn't concentrate on the other lessons for today. I wasn't the only one with prior knowledge, practically the whole class has prior knowledge and some even took Korean for a whole year as compared to me who took merely 10 lessons of conversational Korean.

The difference between us is just that I am honest and they are lying. So why am I being penalised for being honest? Honesty is no longer a virtue? Or should I put it that it is no longer a virtue that NUS accepts? So, now, I learnt a new thing about NUS - never be honest.