material Instance only updates after changes, when the Material Component is expanded or folded

I want to toggle the Shader Type and Alpha (Opaque to fade and Reverse) of a Default Material Instance at a GameObject, while runtime. The switching works after I selected the GameObject in the Editor and expand or fold the Material Component Tab.

Here is my Code: Do i need to update Something? The Interesting Part is void Open and void Close

  private bool open = false;
     public Animator animator;
     public GameObject trainCabin;
     private Material material;
 
     private void Start()
     {
         material = trainCabin.GetComponent<Renderer>().material;
         material.EnableKeyword("_Mode");
         material.EnableKeyword("_Color");
     }
 
     public void OnSelect()
     {
         if (open)
         {
             Close();
         }
         else if (!open)
         {
             Open();
         }
 
     }
 
 
     private void OnMouseDown()
     {
         
         if (open)
         {
             Close();
             Debug.Log("close");
         }
         else if (!open)
         {
             Open();
             Debug.Log("open");
         }
         open = !open;
     }
     private void Close()
     {
         animator.SetTrigger("door");
 
        // trainCabin.GetComponent<Renderer>().material.SetFloat("_Mode", 0);
        // trainCabin.GetComponent<Renderer>().material.SetColor("_Color", new Color(1f, 1f, 1f, 1f));
 
         material.SetFloat("_Mode", 0);
         material = trainCabin.GetComponent<Renderer>().material;
         material.SetColor("_Color", new Color(1f, 1f, 1f, 1f));
 
     }
 
     private void Open()
     {
         animator.SetTrigger("door");
 
 
        // trainCabin.GetComponent<Renderer>().material.SetFloat("_Mode", 2);
        // trainCabin.GetComponent<Renderer>().material.SetColor("_Color", new Color(1f, 1f, 1f, 0.1f));
 
         material.SetFloat("_Mode", 2);
         material = trainCabin.GetComponent<Renderer>().material;
         material.SetColor("_Color", new Color(1f, 1f, 1f, 0.1f));
 
     }