If you are having an issue with the with the actor not being in the level, I would suggest not starting the blueprint on begin play and instead having it start the loop when the actor is spawned and stop the loop if the actor is removed.
If you are having an issue with the with the actor not being in the level, I would suggest not starting the blueprint on begin play and instead having it start the loop when the actor is spawned and stop the loop if the actor is removed.