Simple script not working

Hi. I have a script that counts how many enemies are left and changes the scene when there are no more enemies. However, it doesn’t work, and i can’t find the error, specially because i have a really really similar (like almost the same to be honest) script in another scene and it’s working perfectly. Here’s the code:

public class enemyCountt : MonoBehaviour {

	public static int enemiessCount = 5;

	void Start () {
	}

	void  Update (){
		print("Enemy count is " + enemiessCount ); 

		if(enemiessCount  <= 0)
		{
			SceneManager.LoadScene ("bonus");
		}
}
}

and this is attached to the bullet script:

if (collision.gameObject.tag == "Enemy") {
			enemyCountt.enemiessCount --; 
		}

It’s very unifficient to keep track of the count in Update(),
I’d do something like

 public static void EnemyKilled(){
  enemyCount--
  if(enemyCount <= 0) {
   // do stuff
     }
   }

in class enemyCountt
and on your enemy script

 if (collision.gameObject.tag == "Enemy") {
             enemyCountt.EnemyKilled(); 
         }

Show us ALL the code. even the one of the collision bullet (also i think the bullet of the thing that hits it does not have a rigid body which is necessary by one of the two for it to trigger)