How to use GetContact properly ?

Unity Engine
1

Hi, i use GetContact to retrieve contact point and reflect the object from this contact point. But it looks like not working properly in the long run. Do i use it properly ? What do you suggest ?

-I’ don’t need to retrive all contact points but just the right one.
-Should i reset contact point to get new one each collision or it already gets new points each time on collision ?

public void OnCollisionEnter2D(Collision2D collision)
    {
        ContactPoint2D contact = collision.GetContact(0);

        if (collision.gameObject.tag == "Wall")
        {
            enemyDirection = Vector2.Reflect(enemyDirection, contact.normal);

            rb_Enemy.velocity = enemyDirection * enemyThrust;
        }

        if (collision.gameObject.tag == "Player")
        {
            enemyDirection = Vector2.Reflect(enemyDirection, contact.normal);

            rb_Enemy.velocity = enemyDirection * enemyThrust;
        }
    }
2

Use collision normal & velocity for reflections. Why contacts?