variable increase more than it should

Unity Engine
1

my hero shoots shotgun it has about 12 projectile they set to trigger.When they enter bandit_score should increase 1 but it increases randomly about 6 to 10 . I had to write banditscorebool to fix it but ı dont understand why it didn’t work without banditscorebool

 public void OnTriggerEnter2D(Collider2D collision)
    {
       
        if (collision.gameObject.name == ("pompali_mermi(Clone)"))
        {
      
            GetComponent<AudioSource>().PlayOneShot(hmachete, 0.5f);
            Instantiate(blood, transform.position, Quaternion.identity);
            if (bandit_health>0)
            {
                bandit_health--;

            }
         
      
            if (bandit_health == 0 && banditscorebool))
            {

               banditscorebool = false;
                banditscores.bandit_score++;
                deaddd = false;
                gameObject.layer = LayerMask.NameToLayer("deads");
                GetComponent<Animator>().SetInteger("bandit_dying", 1);
               
            }
    
        }
2

Try putting some Debug.Log() statements in and turn the 12 pellets down to just 1 pellet.

Perhaps your pellets are entering and leaving multiple times, or else you have many colliders and each one is causing a trigger enter callback.