Why can't I get Behavior Tree aborts to work?

Here’s a snippet of my very unfinished behavior tree. The “Player is seen” decorator on the Simple Parallel node is set to abort lower priority if the Blackboard value “SeenPlayer” is set.


Despite the fact that SeenPlayer is in fact set, the behavior tree will keep simulating that branch until it is done.
SeenPlayer is set.
The task it is getting stuck on is comprised of the following:

Am I misunderstanding what “abort” means here? Why does the behavior tree refuse to stop this task?

You need to make sure that you have event abort and finish abort.