Coroutine Problem

public void OnExecuteClick()
    {
        is_moving = true;
        print(is_moving + "1");
        if (move_dir == "up")
        {
            Vector2 up_dir = new Vector2(XCORD, YCORD);
            move_player_cr = StartCoroutine(MovePlayer(up_dir));
        }
        if (move_dir == "down")
        {
            Vector2 down_dir = new Vector2(-XCORD, -YCORD);
            move_player_cr = StartCoroutine(MovePlayer(down_dir));
        }
        if (move_dir == "left")
        {
            Vector2 left_dir = new Vector2(-XCORD, YCORD);
            move_player_cr = StartCoroutine(MovePlayer(left_dir));
        }
        if (move_dir == "right")
        {
            Vector2 right_dir = new Vector2(XCORD, -YCORD);
            move_player_cr = StartCoroutine(MovePlayer(right_dir));
        }
    }


    private IEnumerator MovePlayer(Vector2 direction)
    {
        print(is_moving + "2");
        is_moving = true;

        float elapsed_time = 0;

        orig_pos = transform.position;
        target_pos = orig_pos + direction;

        while(elapsed_time < move_time)
        {
            transform.position = Vector2.Lerp(orig_pos, target_pos, (elapsed_time / move_time));
            elapsed_time += Time.deltaTime;
            print("step" + i);
            yield return null;
        }


        yield return new WaitForSeconds(0.2f);

        transform.position = target_pos;
        if (i > 1)
        {
            i--;
            print(i);
            OnExecuteClick();
        }
        if(i == 1)
        {
            is_moving = false;
        }

        print(is_moving + "4");
    }