How to access my highscore from another scene ?

i want to access my highscore from another script and another scene to my current scene so that i can make a scoreboard link with facebook. But the problem is that i always get my highscore as zero. This is my facebook script ,(check "public void SetScore")

 'using UnityEngine;
 using UnityEngine.UI;
 using System.Collections;
 using System.Collections.Generic;
 
 public class FBholder : MonoBehaviour {
     
     public GameObject UIFBIsLoggedIn;
     public GameObject UIFBNotLoggedIn;
     public GameObject UIFBAvatar;
     public GameObject UIFBUserName;
     private List<object> scoresList = null;
 
     public GameObject ScoreEntryPanel;
     public GameObject ScoreScrollList;
     
     private Dictionary<string, string> profile = null;
     
     void Awake()
     {
         FB.Init (SetInit, OnHideUnity);
     }
     
     private void SetInit()
     {
         Debug.Log ("FB Init done.");
         
         if(FB.IsLoggedIn)
         {
             DealWithFBMenus(true);
             Debug.Log ("FB Logged In");
         }else{
             DealWithFBMenus(false);
         }
         
     }
     
     private void OnHideUnity(bool isGameShown)
     {
         
         if(!isGameShown)
         {
             Time.timeScale = 0;
         }else{
             Time.timeScale = 1;
         }
         
     }
     
     public void FBlogin()
     {
         FB.Login ("email,publish_actions", AuthCallback);
     }
     
     void AuthCallback(FBResult result)
     {
         if(FB.IsLoggedIn){
             Debug.Log ("FB login worked!");
             DealWithFBMenus(true);
         }else{
             Debug.Log ("FB Login fail");
             DealWithFBMenus(false);
         }
     }
     
     void DealWithFBMenus(bool isLoggedIn)
     {
         if(isLoggedIn){
             UIFBIsLoggedIn.SetActive (true);
             UIFBNotLoggedIn.SetActive(false);
             
             // get profile picture code
             FB.API (Util.GetPictureURL("me", 128, 128), Facebook.HttpMethod.GET, DealWithProfilePicture);
             FB.API ("/me?fields=id,first_name", Facebook.HttpMethod.GET, DealWithUserName);
             // get username code
             
         }else{
             UIFBIsLoggedIn.SetActive (false);
             UIFBNotLoggedIn.SetActive(true);
         }
     }
 
     
     void DealWithProfilePicture(FBResult result)
     {
         
         if(result.Error != null)
         {
             Debug.Log ("problem with getting profile picture");
             
             FB.API (Util.GetPictureURL("me", 128, 128), Facebook.HttpMethod.GET, DealWithProfilePicture);
             return;
         }
         
         Image UserAvatar = UIFBAvatar.GetComponent<Image>();
         UserAvatar.sprite = Sprite.Create (result.Texture, new Rect(0,0,128,128), new Vector2(0,0));
         
     }
     
     void DealWithUserName(FBResult result)
     {
         if(result.Error != null)
         {
             Debug.Log ("problem with getting profile picture");
             
             FB.API (  "/me?fields=id,first_name", Facebook.HttpMethod.GET, DealWithUserName);
             return;
         }
         
         profile = Util.DeserializeJSONProfile(result.Text);
         
         Text UserMsg = UIFBUserName.GetComponent<Text>();
         
         UserMsg.text = "Welcome, " + profile["first_name"];
         
         
     }
     
     public void ShareWithFriends()
     {
         FB.Feed (
             linkCaption: "I'm playing this awesome game",
             picture: "http://i58.tinypic.com/vqhdts.png",
             linkName: "Check out this new game",
             link: "http://apps.facebook.com/" + FB.AppId + "/?challenge_brag=" + (FB.IsLoggedIn ? FB.UserId : "guest")
             );
     }
     
     public void InviteFriends()
     {
         FB.AppRequest(
             message: "I challenge you to beat my score.",
             title: "Challenge your friends. "
             );
     }
     
     // All Scores API related Things
     
     public void QueryScores()
     {
         FB.API ("/app/scores?fields=score,user.limit(30)", Facebook.HttpMethod.GET, ScoresCallback);
     }
     
     private void ScoresCallback(FBResult result)
     {
         Debug.Log ("Scores callback: " + result.Text);
         
         
         scoresList = Util.DeserializeScores (result.Text);
         
         foreach (Transform child in ScoreScrollList.transform) 
         {
             GameObject.Destroy (child.gameObject);
         }
         
         foreach (object score in scoresList) 
         {
             
             var entry = (Dictionary<string,object>) score;
             var user = (Dictionary<string,object>) entry["user"];
             
             
             
             
             GameObject ScorePanel;
             ScorePanel = Instantiate (ScoreEntryPanel) as GameObject;
             ScorePanel.transform.parent = ScoreScrollList.transform;
             
             Transform ThisScoreName = ScorePanel.transform.Find ("FriendName");
             Transform ThisScoreScore = ScorePanel.transform.Find ("FriendScore");
             Text ScoreName = ThisScoreName.GetComponent<Text>();
             Text ScoreScore = ThisScoreScore.GetComponent<Text>();
             
             ScoreName.text = user["name"].ToString();
             ScoreScore.text = entry["score"].ToString();
             
             Transform TheUserAvatar = ScorePanel.transform.Find ("FriendAvatar");
             Image UserAvatar = TheUserAvatar.GetComponent<Image>();
             
             
             FB.API (Util.GetPictureURL(user["id"].ToString (), 128,128), Facebook.HttpMethod.GET, delegate(FBResult pictureResult){
                 
                 if(pictureResult.Error != null) // if there was an error
                 {
                     Debug.Log (pictureResult.Error);
                 }
                 else // if everything was fine
                 {
                     UserAvatar.sprite = Sprite.Create (pictureResult.Texture, new Rect(0,0,128,128), new Vector2(0,0));
                 }
                 
             });
             
             
             
         }
 
         
     }
     
     **public void SetScore()
     {
         GameObject High = GameObject.FindGameObjectWithTag("Score");
         ScoreController scoreController = High.GetComponent <ScoreController>();
     
         int high = scoreController.HighScore;
         var scoreData = new Dictionary<string,string> ();
         scoreData ["score"] = high.ToString();
         FB.API ("/me/scores", Facebook.HttpMethod.POST, delegate(FBResult result) {
             Debug.Log ("Score submit result: " + result.Text);
         }, scoreData);
     }**
     
     
 }`

And this is my scoreController script in another scene

 using UnityEngine;
 using System.Collections;
 using UnityEngine.UI;
 
 public class ScoreController : MonoBehaviour {
 
     public Text ScoreText;
     public int score;
     private int Count = 2;
     public Text TotalScoreText;
     public Text HighScoreText;
     public int HighScore;
 
 
     void Start () 
     {
     
         score = -2;
         UpdateScore ();
         AddScore ();        
     }
     
     public    void UpdateScore() 
     {
         ScoreText.text = "Score: " + score;
         TotalScoreText.text = "TOTAL SCORE -: " + score;
         HighScoreText.text = "HIGH SCORE -: " + HighScore; 
     }
     
     public void AddScore( )
     {
         score += Count;
         if(score>PlayerPrefs.GetInt ("HIGHSCORE_KEY",0))
         {
             PlayerPrefs.SetInt ("HIGHSCORE_KEY",score);
         }
         HighScore = PlayerPrefs.GetInt ("HIGHSCORE_KEY",0);
         UpdateScore ();
     }
 
 
 
 
 
 
 }