Console telling me to assign something which is already assigned

This one is really doing my head in - not sure if I am missing something silly.

Straight to the code, which I only just started and already have this issue. The script is called Scoring.js:

 var SpawnPoint : Transform;
 public var prefabObject : GameObject;
 private var clone : GameObject;
 private var offset : Vector3;
 
 var coins : int = 100;
 var canSpawn : boolean = true;
 
 function Start () 
 {
 
 }
 
 function Update () 
 {
     offset = transform.position;
 
     if(Input.GetKeyDown(KeyCode.Space) && coins >0)
         {
             clone = Instantiate(prefabObject, offset, transform.rotation);
             coins --;
             Debug.Log("Coins Left:" + coins);
         }
 }
 
     function OnCollisionEnter(col: Collision)
     {
     //see if the coin hit the trigger for a win
         if (col.gameObject.tag == "coinWin")
         {
             Debug.Log("CoinWin!");
         }
      }

So I have prefabObject assigned in the inspector but the console is spamming me with hundreds of warnings that I need to assign it. What am I doing wrong or what am I misunderstanding?

Edited - forgot to include the error message:

"The variable prefabObject of 'Scoring' has not been assigned. You probably need to assign the prefabObject variable of the Scoring script in the inspector."

Thanks!