I get this error when I try to destroy a blocking volume but the code still works

I am making a level and when you exit a trigger a blocking volume gets removed so you can get to the door. I don’t know how to do it any other way than get blocking volume and to destroy it. I keep getting this error but the code still works.

Error: Blueprint Runtime Error: “Attempted to access BlockingVolume_2 via property BlockingVolume_2_ExecuteUbergraph_TutorialLevel_RefProperty, but BlockingVolume_2 is not valid (pending kill or garbage)”. Node: Destroy Actor Graph: EventGraph Function: Execute Ubergraph Tutorial Level Blueprint: TutorialLevel

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