so, i just got the game and am a good hike into it (second island. done almost everything on it), and i get the the grindstone section. i get the grindstone from north beach camp and bring it back to Bori, who thanks me. it gives me the message about criteria being met for the next seige or whatever, and now its saying i never gave him a grindstone, but it's not in the chest anymore. what gives?