I was dueled when it shouldn't be possible. How is that possible?
If you duel a player, you can be dueled for another 45 minutes afterwards, even if you leave your town, have joined a fort battle or you are in a hotel. Having a bounty on your head also allows other players to attack you, even if you are not in a town. During the advent calendar, if you open the doors too early, the system will put a bounty on you.