Hi,How do I make a 2D laser beam with stable speed ?

I create an olinegame about guys with laser beams in the room ,so i decide to make my laser beam by rigidbody2d that reflect with everything in the room , but when i test it .Sometime my laser has lower speed and stop moving.

what should i do to improve my laser better ?

-laser beam is 2d circle collider with physics2d bounce 0.5

my laser beam code :

 public class LaserBehavior : MonoBehaviour {
 
     // Use this for initialization
     Rigidbody2D _rbLaser;
     [SerializeField]
     GameObject _laser = null;
     public float _speedLaser;
 /*
     void Awake()
     {
         _rbLaser = gameObject.GetComponent<Rigidbody2D>();
         //Invoke("LaserControll",0.1f);
     }
 */
     
     void Start () {
         _rbLaser = gameObject.GetComponent<Rigidbody2D>();
         Invoke("LaserControll",0.1f);
     }
     
     // Update is called once per frame
     void Update () {
         
     }
 
     void LaserControll()
     {
         Vector2 direction = new Vector2(Random.Range(-2, 2), Random.Range(-3, 2)+1);
         _rbLaser.AddRelativeForce(direction*_speedLaser,ForceMode2D.Impulse);
        
     }
 
     void OnCollisionEnter2D(Collision2D other)
     {
         if (other.gameObject.tag == "Player")
         {
             other.gameObject.GetComponent<SpriteRenderer>().color = Color.black;
             other.gameObject.GetComponent<SpriteRenderer>().color = Color.green;
             Debug.Log("destroy");
             Destroy(this);
         }
 
         if (other.gameObject.tag == "Shield")
         {
             Vector2 inDirect = GetComponent<Rigidbody2D>().velocity;
             Vector2 inNormal = other.contacts[0].normal;
             Vector2 reflect = Vector2.Reflect(inDirect, inNormal);
             reflect.Normalize();
 
             _rbLaser.AddRelativeForce(reflect * _speedLaser, ForceMode2D.Impulse);
         }
 
         if (other.gameObject.tag == "ReflectObject")
         {
             //Debug.Log("REFLECT " +other.gameObject.name);
             //Invoke("LaserControll", 0.1f);
             Vector2 inDirect = GetComponent<Rigidbody2D>().velocity;
             Vector2 inNormal = other.contacts[0].normal;
             Vector2 reflect = Vector2.Reflect(inDirect,inNormal);
             reflect.Normalize();
 
             //Debug.Log("inDirection " + inDirect);
             // Debug.Log("REFLECT " + other.gameObject.name+" inNormal" + inNormal);
             //Debug.Log("reflect" + reflect);
 
            // _rbLaser.AddRelativeForce(reflect *(_speedLaser*10), ForceMode2D.Force);
             _rbLaser.AddRelativeForce(reflect * _speedLaser, ForceMode2D.Impulse);
 
             if (_laser != null)
             {
                 GameObject go = Instantiate(_laser, transform.position, transform.rotation);
                 go.name = "Laser";
                 go.GetComponent<SpriteRenderer>().color = Color.white;
             }
         }
     }
 }