Thereis a critical bug here.
I collected all items. When I changed the time on iPhone' settings, I could get the result items. And then came back to start point time, I could cancel the round and restart another round. Repeated this, I collected all the items in a few days. Since I found the bug, This game was not idle game anymore. I changed the time very frequently to get all the items. Lol. But I enjoyed this game. Thank you.