Finding Closest Enemy...

I am trying to make a script that finds enemies closest to my player.

Here is what I have ;-

 function FixedUpdate(){
 Debug.Log(FindClosestEnemy().name);
 }
 
 // Find the closest enemy 
 function FindClosestEnemy() : GameObject { 
     // Find all game objects with tag Enemy 
     var gos : GameObject[]; 
     gos = GameObject.FindGameObjectsWithTag("Enemy"); 
     var closest : GameObject; 
     var distance = Mathf.Infinity; 
     var position = transform.position; 
     // Iterate through them and find the closest one 
     for (var go : GameObject in gos) { 
         var diff = (go.transform.position - position); 
         var curDistance = diff.sqrMagnitude; 
         if (curDistance < distance) { 
             closest = go; 
             distance = curDistance; 
         } 
     } 
     return closest; 
 }

My problem is that the player detects the first enemy and then the second (it gets printed) but when i move back to the first one.. the print doesn't update.. Please help..