Problem with slots [Album of cards]

The drag and drop is done and paste like figures but it is not a method to leave as fixed figures for a specific slot Would anyone know to answer a way to leave the figure fixed to that slot?

Script:DragHandler

 public void OnBeginDrag(PointerEventData eventData)
 {
     itemBeingDragged = gameObject;
     startPosition = transform.position;
     startParent = transform.parent;
     GetComponent<CanvasGroup>().blocksRaycasts = false;
     canvas = GameObject.FindGameObjectWithTag("UI Canvas").transform;
     transform.parent = canvas;
 }

 public void OnDrag(PointerEventData eventData)
 {
     RectTransformUtility.ScreenPointToWorldPointInRectangle(this.GetComponent<RectTransform>(), eventData.position, eventData.enterEventCamera, out startPosition);
     transform.position = startPosition;
 }

 public void OnEndDrag(PointerEventData eventData)
 {
     Debug.Log(transform.parent + " == " + canvas);
     itemBeingDragged = null;
     GetComponent<CanvasGroup>().blocksRaycasts = true;
     if (transform.parent == canvas)
     {
         transform.position = startPosition;
         transform.parent = startParent;
     }
 }

Script:Slot

 public GameObject item{
     get
     {
         if (transform.childCount > 0)
         {
             return transform.GetChild(0).gameObject;
         }
         return null;
     }

 }
 #region IDropMandler Implementation
 public void OnDrop (PointerEventData eventData)
 {
     if (!item)
     {
         DragHandler.itemBeingDragged.transform.SetParent(transform);
     }
 }
 #endregion