Google Admob problem.Banner is not appearing

Unity Engine
,
1

I want to add google admob to my unity game.Using Releases · googleads/googleads-mobile-unity · GitHub But banner not appeared

According to Get started  |  Unity  |  Google for Developers I write simple script and get ids of banner and application from Google Admob Console ( https://apps.admob.com )

    public class ADS : MonoBehaviour
    { 
    string ads_banner_id = "ca-app-pub-6807450626654540/6028463012";
    string appID = "ca-app-pub-6807450626654540~4860573772";

    BannerView bannerView;

    public void InitBanner()
    {
        Debug.Log("InitBanner");
        bannerView = new BannerView(ads_banner_id, AdSize.Banner, AdPosition.Bottom);
        AdRequest request = new AdRequest.Builder().Build();
        bannerView.OnAdLoaded += (sender, args) =>
        {
            Debug.Log("InitBanner OnAdLoaded : " + sender + "->" + sender.GetType() + "\nargs[" + args + "]");
            bannerView.Show();
        };
        bannerView.OnAdFailedToLoad += (sender, args) =>
        {
            Debug.Log("InitBanner OnAdFailedToLoad :" + args.Message);
        };

        bannerView.LoadAd(request);
    }


    void Start()
    {
        MobileAds.Initialize(appID);
    }
}

Unity admob settings:

Manifest:
```csharp
**


** **```**

And Log :

718×221 15.4 KB

What is iam doing wrong?

2

If android<5 try use admob 3.17