I cannot find an AISensingComponent event (preusmably as I’m having to use 4.4, which the project sadly requires and every tutorial seems to be made for).
I assumed it was something to do with the lack of ‘forgetting’ the EnemyActor or LoS-loss, but I haven’t the faintest idea how to clear the BB key (I presume you mean EnemyActor instead of EnemyTarget? I do not see such a value). I will dig around in the blueprints however.