btw, i dont know if this is a bug or not. it seems i cant play together w/ my friend in the same room, but it is fine if we re run dungeon in each room (he created a new room for him self play the game alone).
so basically, when we re playing together :
it stuck there, i cant enter and if i leave the game (via task manager) my friend will go to the dungeon alone. otherwise, if he leave i play alone.