How to make an object's localscale values grow and shrink within a few seconds?

I'm trying to make this 2D sprite pulsate from small to big within 2 seconds. I've went through a few Unity questions and the closest one that works is this:

     public float amplitude;
     public Vector3 scale;


 void Start()
 {
     
     AudioControl.Instance.spin();
     Destroy(gameObject, 2.5f);
 }


 // Update is called once per frame
 void Update () {
     
     for (int i = 0; i < 3; ++i)
     {
         scale[i] = amplitude * Mathf.Sin(Time.time) + 1;
     }
     transform.localScale = scale;

    
 }

}

The problem with this script is that is it going by Time.time and every time the object is instantiated it's not starting off from localScale 1 , but continuing from the same position as the others .