Leaderboard Unity [C#] Help

Here is Leaderboard code but it isnt updating please help

using UnityEngine;
using System.Collections;
using UnityEngine.UI;

public class LeaderBoard : MonoBehaviour
{

    public int highScoreEz;
    public int highScoreMed;
    public int highScoreHard;
    string highScoreKeyEz = "0";
    string highScoreKeyMed = "0";
    string highScoreKeyHard = "0";
    public Text hSEz;
    public Text hSMed;
    public Text hSHard;

    void Start()
    {
        highScoreEz = PlayerPrefs.GetInt(highScoreKeyEz, 0);
        highScoreMed = PlayerPrefs.GetInt(highScoreKeyMed, 0);
        highScoreHard = PlayerPrefs.GetInt(highScoreKeyHard, 0);
    }

    void Update()
    {
        hSEz.text = "" + highScoreEz;
        hSMed.text = "" + highScoreMed;
        hSHard.text = "" + highScoreHard;
    }
}

using UnityEngine;
using System.Collections;
using UnityEngine.UI;

 public class LeaderBoard : MonoBehaviour
 {
 
     public int highScoreEz;
     public int highScoreMed;
     public int highScoreHard;
     string highScoreKeyEz = "0";
     string highScoreKeyMed = "0";
     string highScoreKeyHard = "0";
     public Text hSEz;
     public Text hSMed;
     public Text hSHard;
 
     void Start()
     {
       
     }
 
     void Update()
     {
         highScoreEz = PlayerPrefs.GetInt(highScoreKeyEz, 0);
         highScoreMed = PlayerPrefs.GetInt(highScoreKeyMed, 0);
         highScoreHard = PlayerPrefs.GetInt(highScoreKeyHard, 0);

         hSEz.text = "" + highScoreEz;
         hSMed.text = "" + highScoreMed;
         hSHard.text = "" + highScoreHard;
     }
 }