Player Control and the UI elements

Hy. I trying to make a 2d game, I have a player and some UI buttons, When I press the Pause Button the player change his position, how can avoid this?

My code for player movement:

  if (Input.GetMouseButtonDown(0))
                    started = true;
if (started == true)
           targetFollow = Input.GetTouch(0).position;
           targetFollow = Camera.main.ScreenToWorldPoint(targetFollow);
           transform.position = Vector2.Lerp(transform.position, targetFollow, speed * Time.deltaTime);

What is the code that pauses the game?