GameObject.FindGameObjectsWithTag not working

Hi

Im new to Unity coding and Im building my first application. I am not able to detect game objects with the tag Player though i have assigned the same to my game objects in the Inspector. This is an AR tutorial from YouTube and the entire script can be found on : https://github.com/rubiin/Ar-SpaceShip

The collision script in which the problem is reflecting is mentioned below. The console displays a warning - the variable enemy , enemy 1, etc is assigned but its value is never used

Basically the first four enemy objects are appearing but they are not respawning after they have been destroyed. I am building out on Android

using UnityEngine; using System.Collections;

public class collisionScript : MonoBehaviour {

 // Use this for initialization
 void Start()
 {
     
 }

 // Update is called once per frame
 void Update()
 {
    
 }

 //for this to work both need colliders, one must have rigid body (spaceship) the other must have is trigger checked.
 void OnTriggerEnter(Collider col)
 {
     GameObject explosion = Instantiate(Resources.Load("TinyExplosion", typeof(GameObject))) as GameObject;
     explosion.transform.position = transform.position;
     Destroy(col.gameObject);
     Destroy(explosion, 2);


      if (GameObject.FindGameObjectsWithTag("Player").Length == 0)
      {

        GameObject enemy = Instantiate(Resources.Load("enemy", typeof(GameObject))) as GameObject;
       GameObject enemy1 = Instantiate(Resources.Load("enemy1", typeof(GameObject))) as GameObject;
       GameObject enemy2 = Instantiate(Resources.Load("enemy2", typeof(GameObject))) as GameObject;
       GameObject enemy3 = Instantiate(Resources.Load("enemy3", typeof(GameObject))) as GameObject;

       }

 
     Destroy(gameObject);


 }

}

,Hi

Im new to Unity coding and the GameObject.FindGameObjectsWithTag("Player") line is not working in the script below. In the inspector I have assigned the objects with Player tag. This is an AR tutorial from Youtube and the entire script can be found on:

https://github.com/rubiin/Ar-SpaceShip

using UnityEngine; using System.Collections; public class collisionScript : MonoBehaviour {

 // Use this for initialization
 void Start()
 {
     
 }

 // Update is called once per frame
 void Update()
 {
    
 }

 //for this to work both need colliders, one must have rigid body (spaceship) the other must have is trigger checked.
 void OnTriggerEnter(Collider col)
 {
     GameObject explosion = Instantiate(Resources.Load("TinyExplosion", typeof(GameObject))) as GameObject;
     explosion.transform.position = transform.position;
     Destroy(col.gameObject);
     Destroy(explosion, 2);


      if (GameObject.FindGameObjectsWithTag("Player").Length == 0)
      {

        GameObject enemy = Instantiate(Resources.Load("enemy", typeof(GameObject))) as GameObject;
       GameObject enemy1 = Instantiate(Resources.Load("enemy1", typeof(GameObject))) as GameObject;
       GameObject enemy2 = Instantiate(Resources.Load("enemy2", typeof(GameObject))) as GameObject;
       GameObject enemy3 = Instantiate(Resources.Load("enemy3", typeof(GameObject))) as GameObject;

       }

 
     Destroy(gameObject);


 }

}