I can't get my quest item

I'm doing Star Thief with my friend and we need to kill the insane thief at the last ,so we go into the boss room together and spawned two of them, when we killed them all, he get back the Meteor Shard but i don't. Even i type /kill and go back to the cave, i can't go back into the cave, and the quest told me to give back to the npc, but the npc didn't spawn and i don't have a meteor shard. Even i type /fixquests, it didn't give me the item.
So it is a bug or my fault?

 

Created a bug report, two insane thief shouldn’t be spawned and it’s pretty much a bug discover by a lot of ppl so far.

 

How to create a bug report?

 

https://forums.wynncraft.com/forums/bug-reports.145/