Vector2.right left or down is working, but vector2.up is not working when i hit a box, it's not destroying - i think it's a bug of unity (-_-)

Based on your script image, are you intentionally checking for a GameObject with the name “Box”, rather than with the tag by that name?

Edit: As a side note, you should be able to get slightly better performance by using

GameObject.CompareTag("TagName")

instead of

GameObject.tag == "TagName"