that's because you're using auto
attacking order is generally referring to who attacks first when more than one ninja, such as you and your opponent, or your own ninjas are activating their mysteries, not which mystery is chosen to be activated in auto, cuz that's a totally different story.
in auto, damage causing mysteries, especially barriers are always prioritized over non-damage causing ones.
it has nothing to do with your ninjas initiatives and moving order. such that in auto battle, controlling mysteries such as interruptions will be used when your enemy is activating their mystery, and when your team is not at full health, your medic will be prioritized to use their healing skills etc