ScriptableObject drawing error

Hi, i made a simple PropertyDrawer for a ScriptableObject

Code:

 [CustomPropertyDrawer(typeof(ScriptableObject), true)]
 public class ScriptableObjectDrawer : PropertyDrawer
 {
     // Cached scriptable object editor
     private Editor editor = null;
 
     public override void OnGUI(Rect position, SerializedProperty property, GUIContent label)
     {
         Debug.Log("Drawing " + property.objectReferenceValue);
         Rect rectNorm = position;
 
         if (property.objectReferenceValue != null)
         {
             EditorGUI.LabelField(position, (property.objectReferenceValue as ScriptableObject).name);
         }
         else
         {
             //EditorGUI.PropertyField(position, property, true);
             //return;
             EditorGUI.PropertyField(position, property,true);
             return;
             //EditorGUI.LabelField(position, (property).displayName);
         }
 
         //position.height = EditorGUIUtility.singleLineHeight;
         // Draw foldout arrow
         property.isExpanded = EditorGUI.Foldout(position, property.isExpanded, GUIContent.none);
 
 
 
         // Draw foldout properties
         if (property.isExpanded)
         {
             // Make child fields be indented
             EditorGUI.indentLevel++;
             if ((property.objectReferenceValue == null))
             {
                 position.y += EditorGUIUtility.singleLineHeight;
                 position.height = EditorGUIUtility.singleLineHeight;
                 EditorGUI.PropertyField(position, property);
                 position = rectNorm;
             }
 
             if (property.objectReferenceValue != null)
             {
       
                 //(property.objectReferenceValue as ScriptableObject).name = EditorGUI.TextField(position, "name", (property.objectReferenceValue as ScriptableObject).name);
 
                 // Draw object properties
                 if (!editor)
                 {
                     Editor.CreateCachedEditor(property.objectReferenceValue, null, ref editor);
                 }
 
                 if (editor != null)
                 {
                     editor.OnInspectorGUI();
                 }
             }
 
             // Set indent back to what it was
             EditorGUI.indentLevel--;
         }
     }
 
 
 
 }

And i also made to Scriptable Object children: 1) GameRule :

 [CreateAssetMenu(fileName = "Game rule", menuName = "Game rules/game rule")]
 public class GameRule : ScriptableObject
 {
     [System.Serializable]
    public enum TriggerMode
     {
         //TBD
         OneToTrigger,
         AllToTrigger
     }
 
     [System.Serializable]
    public enum ActionMode
     {
         //TBD
         OneToDo,
         AllToDo
     }
 
     //Triggers : List<EventTrigger> TriggerMode : Enum Actions : List<GameAction> ActionMode : Enum
     //Maybe TriggerAction pair is better
     public TriggerMode triggerMode;
     public ActionMode actionMode;
 }

2) Level :

 [CreateAssetMenu(fileName = "levelSO", menuName = "Levels/Level")]
 public class Level : ScriptableObject
 {
     public string Name;
     public List<GameRule> Rules;
 }
 

Now , when i try to edit my SO level i get this error: ArgumentException: Getting control 1's position in a group with only 1 controls when doing repaint And it stops drawing...

Can somebody pls explain me why this kind of error appears and is this a good practice to store SO inside others So. Thanks