Player not spawning in right place.

Hello Im trying to make my player spawn in the place that he left the game in but he is always spawning in mainspawn no matter what I don't know whats wrong I checked all the tags and they are correct please Someone Help!!!

Heres my script:

 using UnityEngine;
 using System.Collections;
 
 public class StatTracker : MonoBehaviour {
 
     public float PosX;
     public float PosY;
     public float PosZ;
     
     public GameObject SpawnMain;
     
     public GameObject Player;
     public GameObject PlayerPre;
     
     public Vector3 PlayerPos;
     
     void Start(){
         SpawnMain = GameObject.FindGameObjectWithTag("MainSpawn");
         
         PosX = PlayerPrefs.GetFloat("X");
         PosY = PlayerPrefs.GetFloat("Y");
         PosZ = PlayerPrefs.GetFloat("Z");
         
         PlayerPos.x = PosX;
         PlayerPos.y = PosY;
         PlayerPos.z = PosZ;
         
         if(PlayerPos.z != 0 && PlayerPos.x != 0){
         Instantiate(PlayerPre,PlayerPos,Quaternion.identity);
         }
         else{
         Instantiate(PlayerPre,SpawnMain.transform.position,Quaternion.identity);
         }
     }
     
     void Update(){
         Player = GameObject.FindGameObjectWithTag("Player");
             PosX = Player.transform.position.x;
             PosY = Player.transform.position.y;
             PosZ = Player.transform.position.z;
             PlayerPrefs.SetFloat("X",PosX);
             PlayerPrefs.SetFloat("Y",PosY);
             PlayerPrefs.SetFloat("Z",PosZ);
         
     }
     
 }

Updated Script:

 using UnityEngine;
 using System.Collections;
 using System.Collections.Generic;
 
 public class StatTracker : MonoBehaviour {
     
     public float PosX;
     public float PosY;
     public float PosZ;
     
     public Vector3 Spawn;
     
     private bool isPaused = false;
     private bool isPauseMenu = true;
     
     public GameObject Prefab_Player;
     
     public GameObject Spawn_1;
     
     public GameObject Player;
     
     void Start(){
         PosX = PlayerPrefs.GetFloat("X");
         PosY = PlayerPrefs.GetFloat("Y");
         PosZ = PlayerPrefs.GetFloat("Z");
         
         Spawn.x = PosX;
         Spawn.y = PosY;
         Spawn.z = PosZ;
         
         if(Spawn != Vector3.zero){
             Instantiate(Prefab_Player,Spawn,Quaternion.identity);
         }
         else{
             Instantiate(Prefab_Player,Spawn_1.transform.localPosition,Quaternion.identity);
         }    
         Player = GameObject.FindGameObjectWithTag("Player");
     }
     
     
     void Update(){
         Player = GameObject.FindGameObjectWithTag("Player");
         PlayerPrefs.SetFloat("X",Player.transform.position.x);
         PlayerPrefs.SetFloat("Y",Player.transform.position.y);
         PlayerPrefs.SetFloat("Z",Player.transform.position.z);
     }
 }