How to switch the beahviour tree branch upon Bool change in Blueprints

Here Is my blueprint that changes the speed of my AI when They see the player.

But the problem is the decorator on the top selector allways says that the Bool is not set, even though i can watch the bool change from true to false at runtime how can io use this bool to stop the tree running down this branch the minute they see him? So i want the left branch to be stopped when they see him and the right branches executed because of this

You can add an Observer to the Selector Composite with the Blackboard check for IsSeen. If you click the Composite, then the Blackboard check you’ve made. You’ll see Notify Observer at the very top. Change this to On Result Change, then change Observer aborts self.

What should then happen is once the IsSeen is updated by your Pawn on OnSeePawn, the observer will abort the composite it belongs to.

Let me know if you understand!

Thanks,
Peter L. Newton

Thanks for the quick reply, It worked!