Drag object without centering to mouse

Scripting
1

Hello,
after reading some example to move an object without centering it to mouse cursor, I still have a problem, while dragging the object becomes more and more distant to cursor.
Does anyone can help me?

this is my code:

public void OnBeginDrag(PointerEventData eventData)
    {
        Debug.Log("OnBeginingDrag");
        distance = Camera.main.ScreenToWorldPoint(new Vector3(Input.mousePosition.x, Input.mousePosition.y,Camera.main.WorldToScreenPoint(transform.position).z)) - transform.position;
    }

    public void OnDrag(PointerEventData eventData)
    {
        Debug.Log("OnDrag");
        Vector3 distance_to_screen = Camera.main.WorldToScreenPoint(transform.position);
        Vector3 pos_move = Camera.main.ScreenToWorldPoint(new Vector3(Input.mousePosition.x, Input.mousePosition.y, distance_to_screen.z ));
        this.transform.position = new Vector3( pos_move.x - distance.x , pos_move.y - distance.y, transform.position.z );

    }

Thank you

2

You have to store the position at which the drag started, and then move the object by difference, not by an absolute.