When trading with villagers, or not even trading with them at all, a very small amount of them will just have their GUI's flash on my screen then they disappear almost instantly. I reloaded the game a few times and it still wouldn't work. Even a villager I got to the master level all of a sudden wouldn't trade with me because of this bug. I thought it was my resource pack too, but i turned on the default one and it still was occurring. I don't know whats causing it, but all I know this happens to some villagers and then it may occur randomly to another,