Coc now has a lock on the target of tribal warfare and can add comments. What does that mean?

Just tell someone which one you want to play, and the other one can say something about playing. Of course, when you target someone to make a phone call, the system will only remind him and will not stop him from making a phone call. Of course, if you hit the locked target, the enemy's lock will disappear and you can't lock him again.