Ok, your first blueprint should work. “BeginOverlap” means when the player enters the trigger box. If the player stands still ANYWHERE in the box (the corner, included), the “EndOverlap” event should not fire. This means that somehow, while standing still, the player is repeatedly entering and exiting the trigger box area.
TheSpaceMan had a good potential way this could happen which you have not addressed. If the character has an idle animation, they may “swing” back and forth while standing still. And if somehow your player capsule did not have collision enabled on it, the game may only be able to use the skeletal mesh for collision. So as the character’s idle animation swings him forward, his arm enters the trigger box and the door opens. As the character swings back, the arm leaves and the door closes.
If you do not have an idle animation set up or your player capsule has collision set on it, this will not be the issue.
This confuses me a little bit. Perhaps you can give a screenshot of the components panel so we can see the door? This is what I’m imagining (I’m at work and have only MS Paint available):
Sliding door in the middle, slides to the left. The dotted line is the trigger box. What do you mean when you say the player “hit two edges”?