Twenty() ia a button ,in my game when i press it ,on the consoole it desplays :Dummy ShowRewardBasedVideoAd, but when i build the game and I press the button ,nothing happens (on the android device)

using System.Collections; using System.Collections.Generic; using UnityEngine; using GoogleMobileAds; using GoogleMobileAds.Api; using UnityEngine.SceneManagement;

public class videoAd : MonoBehaviour {

 public static int Twen;
 private RewardBasedVideoAd rewardBasedVideo;

 // Use this for initialization
 void Start () {

     RequestInterstitial();
     Twen = 15;
     rewardBasedVideo = RewardBasedVideoAd.Instance;

     rewardBasedVideo.OnAdRewarded += HandleOnReward;

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

 public void Twenty()
 {
     ShowInterstitial();

 }

 private void ShowInterstitial()
 {

     if (rewardBasedVideo.IsLoaded())
     {
         rewardBasedVideo.Show();
     }
 }

 private void RequestInterstitial()
 {

if UNITY_EDITOR

    string adUnitId = "unused";

elif UNITY_ANDROID

    string adUnitId = " ca-app-pub-1324966xxxxxxxxxxxxxxxxxxxxx";

elif UNITY_IPHONE

    string adUnitId = "ca-app-pub-39402560xxxxxxxxxxxxxxxxxxxx";

else

    string adUnitId = "unexpected_platform";

endif

     RewardBasedVideoAd rewardBasedVideo = RewardBasedVideoAd.Instance;

     AdRequest request = new AdRequest.Builder().Build();
     rewardBasedVideo.LoadAd(request, adUnitId);
 }

 public void HandleOnReward(object sender, Reward args)
 {
     PlayerPrefs.SetInt("Points", Gamecontroller.PointsNow + Twen);
     SceneManager.LoadScene(SceneManager.GetActiveScene().buildIndex);
 }

}