Seto boss on naruna dungeon (punika) is not dropping anything

I don’t know what is happening but: the boss stay at 1hp on his circus zone, i can see the loot but instantly, the cinematic appear, and no loot right after
it happened on both hard and normal version on my demonic " Pokokakola"
and it just happened to my warrior “pokon” on hard mode
please, fix this, and give me back my precious loot