How can I get a gameobject to be deactivated and a cube gameobject with a particle Emmitter to activate?

The problem that is occurring is that my public gameObject Fire will not work unless it has a prefab. even with said prefab the object will not go from "Not Activated to Activated" My code is: public class LaserCollision : MonoBehaviour { public GameObject fire; void OnTriggerEnter(Collider other) { if (other.gameObject.CompareTag("SD")) { other.gameObject.SetActive(false); fire.gameObject.SetActive(true); Debug.Log("boom"); } else { fire.gameObject.SetActive(false); } }

}