Editor - Displaying GUI lines between two points using switch case

Hello,

I am trying to implement an editor script that would display GUI lines between any two points in the editor. I have three empty game objects as Vector3 points (A, B and C), and for example, if button #1 is pressed, a value of integer "switchCase" will be set to 1, and according to the switch case statement, it will display a line between point A and point B. If button #2 is pressed, "switchCase" is set to 2, and it will display lines between point A and B, and between point B and C, and so on.

The problem I have is that when I press the buttons - nothing happens in the editor. I can see that the value of "switchCase" is changing correctly in the inspector, but the lines are not showing.

If I input the value straight in the inspector, it works as it should, but my goal is to have the value changing when the button is pressed, rather that me changing the value in the inspector manually.

Hopefully my question makes sense. Any help will be appreciated!

Here is the Editor script:

 using UnityEngine;
 using System.Collections;
 using UnityEditor;
 using System.Collections.Generic;
 using UnityEditor.AnimatedValues;
 using System.Linq;
 
 [CustomEditor(typeof(LineTest))]
 public class LineTestInspector : Editor
 {    
     public LineTest myScript;
     
     public void OnSceneGUI()
     {
 
         Handles.color = Color.red;
 
         switch (myScript.switchCase)
         {    
             case 1:
 
                 GameObject posAobj = GameObject.Find("PointA");
                 GameObject posBobj = GameObject.Find("PointB");
 
                 myScript.posA = posAobj.transform.position;
                 myScript.posB = posBobj.transform.position;
 
                 Handles.DrawLine(myScript.posA, myScript.posB);
 
                 break;
 
             case 2:
 
                 GameObject posCobj = GameObject.Find("PointC");
 
                 myScript.posC = posCobj.transform.position;
 
                 Handles.DrawLine(myScript.posA, myScript.posB);
                 Handles.DrawLine(myScript.posB, myScript.posC);
 
                 break;
         }
 
     public override void OnInspectorGUI()
     {
         DrawDefaultInspector();
         
         if (GUILayout.Button("Draw First Line"))
         {
             myScript.switchCase= 1;
             Debug.Log("Switch - 1");
         }
 
         if (GUILayout.Button("Draw Second Line"))
         {
             myScript.switchCase = 2;
             Debug.Log("Switch - 2");
         }
 
         if (GUILayout.Button("Reset switchCase"))
         {
             myScript.switchCase = 0;
             Debug.Log("Switch - 0");
         }
     }
 }
 

And the Mono script:

      using System.Collections;
      using System;
      using System.Collections.Generic;
      using UnityEngine;
 
      public class LineTest : MonoBehaviour {
     
         public Vector3 posA;
         public Vector3 posB;
         public Vector3 posC;
     
         public int switchCase;
     
     }