Killed arbiter of ash while I was dead

After I killed him while I was in my revive screen, I saw the loot drop so I was happy, pressed revive and saw the arena fully reset.
Thought thats weird, but i can just kill him again, after which he promptly got a heartattack or something and died, leaving behind only the arbiter atlas book and nothing else, while also preventing me from touching the quest item thing.
I was able to claim the atlas book from doryani anyway, but im annoyed i didnt get to pick up my loot.

same problem happened to me today :( i had a morior on the ground im so sad now...