Trouble destroying a instantiated Prefab?

Hey, so I have a game where two players battle each other by colliding. After each collision their health decreases a little and when it hits 0 then they will be destroyed. So the way I have it set up is my game manager script instantiates both players from a set of prefabs from the void start () function. Then the gamemanager also keeps track of health and when health = 0 destroys the player. I use a separate script on a child object in each player object that determines when to activate the function damage () which does the heavy lifting in the gamemanager script. So basically the player calls to the manager each time its hit.

The problem is that even though I have spent the last 5 hours researching it, the instantiated prefab wont be destroyed - the function its in is calling itself but its just not being destroyed. Im wondering if this is a more complex issue involving calling a public void function from another script thats also custom or maybe its a issue with instantiating objects from the start () function.

 void Start () {
 
         PlayerOne = (GameObject) Instantiate (Player1, Player1Spwn.transform.position, Quaternion.identity);
         PlayerTwo = (GameObject) Instantiate (Player2, Player2Spwn.transform.position, Quaternion.identity);
 
 
 
 
     }
 
     void Update () {
 
         if (Input.GetKeyDown (KeyCode.G)) {
             Debug.Log (health1);
         }
 
 
 
     }
 
 
     public void DamageP1 () {
 
 
             health1 = health1 - 10;
             Debug.Log (health1);
          if (health1 <= 0) {
             Destroy (PlayerOne);
             Debug.Log ("hey");
         }
 
     }
 
 
     public void DamageP2 () {
 
 
             health2 = health2 - 10;
             Debug.Log (health2);
      if (health2 <= 0) {
             Destroy (PlayerTwo);
             Debug.Log ("hey");
         }
 
     }
 }

Here is the call function thing in the child object:

 void OnTriggerEnter2D (Collider2D theOtherCollider) {
         if (theOtherCollider.gameObject.tag == "Player2") {
             script.DamageP2 ();
          
         }

Thanks in advance!!!