General

Old Cygnus Knights and new 4th job advancement

So I have a level 120 NW from 2-3 years back and I thought it'd be a good idea to advance it to 4th job. The only problem is, I've completed the quest for it 3 years ago. I have a 4th job skill tab but there are no skills in the tab. I kept googling around but every search came up with the same answer: Black Witch quest in Aqua Road (which is completed). How do I go about 'fixing' my Nightwalker?

Thanks