Flutter: my flutter app is crashed on launch after I implement google interstitial ads

Question

I am building my first flutter app. I try to implement google interstitial add in my app. But the app is crashing on launch. I used Android emulator to launch the app.

I added this in my AndroidManifest.xml file:

<meta-data
            android:name="com.google.android.gms.ads.APPLICATION_ID"
            android:value="ca-app-pub-3940256099942544~3347511713"/>

and in build.gradle:

defaultConfig {
        applicationId "mando.minu_app"
        minSdkVersion 23
        targetSdkVersion flutter.targetSdkVersion
        versionCode flutterVersionCode.toInteger()
        versionName flutterVersionName
        targetSdkVersion 34
        multiDexEnabled true
    }

How can I fix it? Thanks.