Aion Riftshade

Hello, 

I stumbled across a bug during the quest "a captive flame". I am unable to spawn Agnita because the right chalice is bugged and I can't click on it (screenshot). I know it's the right one because the 4 others spawn mobs instead of Agnita. I've restarted the dungeon 3 times and the issue is still there. What can I do?

Nevermind, after a few tries another chalice was the good one. But there's still one chalice floating around. Took me 5 tries to loot the item.