AdMob Interstitial is not fit for screen

Hi, I just followed the steps found on Interstitial ads | Unity | Google Developers to create an interstitial (full screen) ad.

This is the code I used:

InterstitialAd interstitial;
string AndroidId = "ca-app-pub-3940256099942544/8691691433";
string IphoneId;

void RequestInterstitial(){
    string adUnitId = string.Empty;

    #if UNITY_ANDROID || UNITY_EDITOR
        adUnitId = AndroidId;
    #elif UNITY_IPHONE || UNITY_EDITOR
        adUnitId = IphoneId;
    #endif

    // Initialize an InterstitialAd.
    interstitial = new InterstitialAd(adUnitId);
   
    // Called when an ad request has successfully loaded.
    interstitial.OnAdLoaded += OnAdLoaded;
    // Called when an ad request failed to load.
    interstitial.OnAdFailedToLoad += OnAdFailedToLoad;
    // Called when an ad is shown.
    interstitial.OnAdOpening += OnAdOpening;
    // Called when the ad is closed.
    interstitial.OnAdClosed += OnAdClosed;

    // Create an empty ad request.
    AdRequest request = new AdRequest.Builder().Build();
    // Load the interstitial with the request.
    interstitial.LoadAd(request);
}

// somewhere in the code after loading the ad
interstitial.Show();

But as you can see in the photo below that the image is not showing properly

What did I do wrong? Is there a way to set the size of the ad of an interstitial ad? from what I’m aware, it is supposedly fullscreen

i think it is a problem with device orientation settings. go to player settings> android settings> resolution and presentation> orientation settings. check other settings in that too to make sure everything is fine.