Messaging System In Unity

I am trying to create a messaging system in Unity in order to communicate things that happen in the game with events. For now what I want to do is call an event when there is collision between the player's bullets and the enemies. While this actually works, the problem I am having is that since the script is using a messaging system, the exact same event is shared and so does the health for both enemies. So when I shoot on fore example, they all lose the same amount of health. Do you know any way to prevent that?

Code for Event Manager

 using System.Collections;
 using System.Collections.Generic;
 using UnityEngine;
 using UnityEngine.Events;
 
 [System.Serializable]
 public class TypedEvent : UnityEvent<object> { }
 
 public class EventManager : MonoBehaviour
 {
     private Dictionary<string, UnityEvent> eventDictionary;
 
     private static EventManager eventManager; 
     // Start is called before the first frame update
     public static EventManager instance
     {
         get
         {
             if(!eventManager){
                 eventManager = FindObjectOfType(typeof(EventManager)) as EventManager;
                 if (!eventManager)
                 {
                     Debug.LogError("There needs to be one active EventManager script on a GameObject in the scene");
                 }
                 else
                 {
                     eventManager.Init();
                 }
             }
 
             return eventManager;
         }
     }
 
     private void Init()
     {
         if(eventDictionary == null)
         {
             eventDictionary = new Dictionary<string, UnityEvent>();
         }
     }
 
     // Unity Action allows for dynamically calling multiple functions(they must have no arguments)
     public static void StartListening(string eventName,UnityAction listener)
     {
         UnityEvent thisEvent = null;
         if(instance.eventDictionary.TryGetValue(eventName,out thisEvent))
         {
             thisEvent.AddListener(listener);
         }
         else
         {
             thisEvent = new UnityEvent();
             thisEvent.AddListener(listener);
             instance.eventDictionary.Add(eventName, thisEvent);
         }
     }
 
     public static void StopListening(string eventName,UnityAction listener)
     {
         if (eventManager == null) 
             return;
         UnityEvent thisEvent = null;
         if(instance.eventDictionary.TryGetValue(eventName,out thisEvent))
         {
             thisEvent.RemoveListener(listener);
         }
     }
 
     public static void TriggerEvent(string eventName)
     {
         UnityEvent thisEvent = null;
         if(instance.eventDictionary.TryGetValue(eventName,out thisEvent))
         {
             thisEvent.Invoke();
         }
     }
 
 }

Code for Enemy Health

 using System.Collections;
 using System.Collections.Generic;
 using UnityEngine;
 using UnityEngine.UI;
 using UnityEngine.Events;
 
 public class enemyDepleteHeatlh : MonoBehaviour
 {
     private int enemyDamage;
 
     [SerializeField]
     private float maxHealth;
 
     [SerializeField]
     private float curHealth;
 
     private GameObject gun;
 
     [SerializeField]
     Slider healthBar;
 
     private UnityAction onTakeDamage;
 
     //public float damageToEnemy;
 
     // Start is called before the first frame update
     private void Awake()
     {
         gun = GameObject.FindGameObjectWithTag("gun");
         enemyDamage = gun.GetComponent<playerShooting>().damage;
         onTakeDamage = new UnityAction(OnTakeDamage);
         GameManager.enemyHealth = maxHealth;
         maxHealth = curHealth;
         curHealth = healthBar.value;
     }
 
     private void OnEnable()
     {
         EventManager.StartListening("TakeDamage", onTakeDamage);
     }
 
     private void OnDisable()
     {
         EventManager.StopListening("TakeDamage", onTakeDamage);
     }
 
     // Update is called once per frame
     void Update()
     {
         healthBar.value = this.curHealth;
 
         
 
         if(curHealth <= 0)
         {
             Destroy(this.gameObject);
         }
 
         if(curHealth > maxHealth)
         {
             this.curHealth = maxHealth;
         }
 
     }
 
     private void OnTakeDamage()
     {
         Debug.Log("Bullet has collided");
         this.curHealth -= enemyDamage;
     }

Enemy Health Emitter

 using System.Collections;
 using System.Collections.Generic;
 using UnityEngine;
 
 public class enmyHeatlhdepleteEmitter : MonoBehaviour
 {
 
     private void OnTriggerEnter(Collider other)
     {
         if (other.gameObject.tag == "Enemy")
         {
             EventManager.TriggerEvent("TakeDamage");
         }
     }
 }