Moving object

I have a script which create object on start, then I want to move that object, but it doesn’t work
please tell me where is my mistake

    var ball: Transform;
    var speed : float = 15;
    var z : float = -0.55;
    var y = 94;
    
    function Start() {
    	Instantiate(ball, Vector3 (0, y, z), Quaternion.identity);
    }
    
    function Update () {
    	var direction = ball.transform.right;
    	var x = (Input.GetAxis("Horizontal") * direction * Time.deltaTime * speed);
    
    	ball.transform.position = x;
    	
    }

You are trying to transform your prefab “ball”, not your instantiated object.

Use something like this:

myBall=Instantiate(ball, ...) as Transform;

and then modify myBall instead.