Trying to get reversed movement on collision on Unity2 - unity3d

Question

so I am trying to make a shooting machine that shoots bullet and bullet gets back from the same way it went through when hitting the wall without speeding up and without changing angle (just the opposite way)
i added force and tried many ways but nothing works , please help
here is my code (the last one) even though i normalized the force but i still feel like its speeding up
public Rigidbody2D rb;
private float bulletForce = 20f;
private bool collided;
Vector2 dir;
private void Awake()
{
instance = this;
rb = gameObject.GetComponent<Rigidbody2D>();
dir = transform.up;
}
void Update()
{
rb.AddForce(dir.normalized * bulletForce * Time.deltaTime, ForceMode2D.Impulse);
}
private void OnCollisionEnter2D(Collision2D other)
{
if (other.gameObject.CompareTag("Edge"))
{
dir = Vector2.Reflect(rb.position, other.contacts[0].normal);
rb.velocity = dir.normalized * bulletForce;
transform.up = dir.normalized;
}
}
this is wanted results explanation
this is current results explanation

Answer 1

If you just want to exactly invert the direction than
rb.velocity = -rb.velocity;
transform.up = rb.velocity;
and of course it is speeding up since you constantly add force in
void Update()
{
rb.AddForce(dir.normalized * bulletForce * Time.deltaTime, ForceMode2D.Impulse);
}
why don't you just disable any friction for this bullet and set an initial velocity once?

Answer 2

public class CollideReflector : MonoBehaviour
{
[SerializeField] Rigidbody2D rb;
[SerializeField] Vector2 direction;
[SerializeField] float bulletForce = 20f;
[SerializeField]float smooth;
private bool collided;
// STARTER
private void Awake()
{
instance = this;
rb = gameObject.GetComponent<Rigidbody2D>();
direction = transform.up;
}
void Update()
{
rb.AddForce(direction.normalized * bulletForce * Time.deltaTime, ForceMode2D.Impulse);
}
private void OnCollisionEnter2D(Collision2D other)
{
if (other.gameObject.CompareTag("Edge"))
{
var x = Quaternion.Euler(transform.eulerAngles.x, transform.eulerAngles.y, transform.eulerAngles.z);
Quaternion target = -x;
transform.rotation = Quaternion.Slerp(transform.rotation, x, Time.deltaTime * smooth);
rb.AddForce(-direction.normalized * bulletForce * Time.deltaTime, ForceMode2D.Impulse);
}
}
}