unity – How to access a property in an object’s method called by UnityEvent.Invoke()?

I have 3 objects in my Unity scene:

• Planet, with script Planet, property actionableModel and method stopBuilding()

  public class Planet : MonoBehaviour
  {
      private GameObject _actionableModel;
  
      // ...
  
      public void stopBuilding()
      {
          // For debugging only
          Planet planet = GameObject.Find("Planet").GetComponent<Planet>();
          Debug.Log(planet.actionableModel);
          Debug.Log(this.actionableModel);
  
      }
  }
  

• Actionable with script Actionable which has UnityEvent property onClick, which calls stopBuilding() on a click event

  public class Actionable : MonoBehaviour
  {
      public class OnClick : UnityEvent<GameObject> { }
      public OnClick onClick = new OnClick();
  
      // ...
  
      void OnMouseDown()
      {
          onClick.Invoke(gameObject);
      }
  }
  

• A Button, which calls stopBuilding() on click event.

When stopBuilding() is invoked by the button click, everything works as expected, both Debug.Log() calls print the correct actionableModel. However, when the method is invoked via the Actionable script, the second log Debug.Log(this.actionableModel) prints null (even though this object is still Planet for some reason). Since the first log Debug.Log(planet.actionableModel) still prints the correct value, I assume this is not a problem with the actual value of the property. (I have only a single “Planet” object)

From my experience outside C# and Unity, in which I have only humble experience, I would assume that the context here is improper and that I would need to pass it when I am invoking the method. There seems to be no way to do that though in UnityEvent object.

How can I invoke the UnityEvent callback in the same way as Button does, such that I have access to actionableModel in stopBuilding?