true initialized bool is false after compiling

Hey, i have a really strange issue.
The bool “firstFrame” is initialized to true, but after compilation is is set to false.
The if condition is allways false in play mode and the Debug.Log is never reached.

Could this have anything to with the fact that the class is a child of an abstract class?
Am I missing something?

 public class ActionAgentWalkTo : AAction {

        private bool firstFrame = true;
    
        public override bool Execute() {
            if (firstFrame) {
                Debug.Log("First Frame")
                firstFrame = false;
            }
    
            ...
        }
    }

Okay, I found the issue.
An Instance of this class is living in the scene and the value didn’t get reset for it. When I delete the instance and add a new one, the bool is set to true.