googleads-mobile-flutter: 🐛Ad for following adId already exists: 0

Bug report

Describe the bug This error appears if I set the adUnitId to literally anything. I’ve tried setting the property to ‘hi’ and a bunch of other stuff but it somehow still appears. And if I set it to a valid ad id it continues to appear and the ad never shows.

E/MethodChannel#plugins.flutter.io/google_mobile_ads( 6263): java.lang.IllegalArgumentException: Ad for following adId already exists: 0
E/MethodChannel#plugins.flutter.io/google_mobile_ads( 6263):    at io.flutter.plugins.googlemobileads.AdInstanceManager.trackAd(AdInstanceManager.java:66)
E/MethodChannel#plugins.flutter.io/google_mobile_ads( 6263):    at io.flutter.plugins.googlemobileads.GoogleMobileAdsPlugin.onMethodCall(GoogleMobileAdsPlugin.java:266)
E/MethodChannel#plugins.flutter.io/google_mobile_ads( 6263):    at io.flutter.plugin.common.MethodChannel$IncomingMethodCallHandler.onMessage(MethodChannel.java:233)
E/MethodChannel#plugins.flutter.io/google_mobile_ads( 6263):    at io.flutter.embedding.engine.dart.DartMessenger.handleMessageFromDart(DartMessenger.java:85)
E/MethodChannel#plugins.flutter.io/google_mobile_ads( 6263):    at io.flutter.embedding.engine.FlutterJNI.handlePlatformMessage(FlutterJNI.java:692)
E/MethodChannel#plugins.flutter.io/google_mobile_ads( 6263):    at android.os.MessageQueue.nativePollOnce(Native Method)
E/MethodChannel#plugins.flutter.io/google_mobile_ads( 6263):    at android.os.MessageQueue.next(MessageQueue.java:335)
E/MethodChannel#plugins.flutter.io/google_mobile_ads( 6263):    at android.os.Looper.loop(Looper.java:183)
E/MethodChannel#plugins.flutter.io/google_mobile_ads( 6263):    at android.app.ActivityThread.main(ActivityThread.java:7656)
E/MethodChannel#plugins.flutter.io/google_mobile_ads( 6263):    at java.lang.reflect.Method.invoke(Native Method)
E/MethodChannel#plugins.flutter.io/google_mobile_ads( 6263):    at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:592)
E/MethodChannel#plugins.flutter.io/google_mobile_ads( 6263):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:947)
E/flutter ( 6263): [ERROR:flutter/lib/ui/ui_dart_state.cc(177)] Unhandled Exception: PlatformException(error, Ad for following adId already exists: 0, null, java.lang.IllegalArgumentException: Ad for following adId already exists: 0
E/flutter ( 6263):      at io.flutter.plugins.googlemobileads.AdInstanceManager.trackAd(AdInstanceManager.java:66)
E/flutter ( 6263):      at io.flutter.plugins.googlemobileads.GoogleMobileAdsPlugin.onMethodCall(GoogleMobileAdsPlugin.java:266)
E/flutter ( 6263):      at io.flutter.plugin.common.MethodChannel$IncomingMethodCallHandler.onMessage(MethodChannel.java:233)
E/flutter ( 6263):      at io.flutter.embedding.engine.dart.DartMessenger.handleMessageFromDart(DartMessenger.java:85)
E/flutter ( 6263):      at io.flutter.embedding.engine.FlutterJNI.handlePlatformMessage(FlutterJNI.java:692)
E/flutter ( 6263):      at android.os.MessageQueue.nativePollOnce(Native Method)
E/flutter ( 6263):      at android.os.MessageQueue.next(MessageQueue.java:335)
E/flutter ( 6263):      at android.os.Looper.loop(Looper.java:183)
E/flutter ( 6263):      at android.app.ActivityThread.main(ActivityThread.java:7656)
E/flutter ( 6263):      at java.lang.reflect.Method.invoke(Native Method)
E/flutter ( 6263):      at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:592)
E/flutter ( 6263):      at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:947)
E/flutter ( 6263): )
E/flutter ( 6263): #0      StandardMethodCodec.decodeEnvelope (package:flutter/src/services/message_codecs.dart:582:7)
E/flutter ( 6263): #1      MethodChannel._invokeMethod (package:flutter/src/services/platform_channel.dart:159:18)
E/flutter ( 6263): <asynchronous suspension>
E/flutter ( 6263): #2      MethodChannel.invokeMethod (package:flutter/src/services/platform_channel.dart:332:12)
E/flutter ( 6263): #3      AdInstanceManager.loadNativeAd (package:google_mobile_ads/src/ad_instance_manager.dart:172:20)
E/flutter ( 6263): #4      NativeAd.load (package:google_mobile_ads/src/ad_containers.dart:576:27)
E/flutter ( 6263): #5      NativeAdState.initState.<anonymous closure> (package:discord_bots/widgets/global/native_ad_widget.dart:36:65)
E/flutter ( 6263): #6      new Future.delayed.<anonymous closure> (dart:async/future.dart:326:39)
E/flutter ( 6263): #7      _rootRun (dart:async/zone.dart:1182:47)
E/flutter ( 6263): #8      _CustomZone.run (dart:async/zone.dart:1093:19)
E/flutter ( 6263): #9      _CustomZone.runGuarded (dart:async/zone.dart:997:7)
E/flutter ( 6263): #10     _CustomZone.bindCallbackGuarded.<anonymous closure> (dart:async/zone.dart:1037:23)
E/flutter ( 6263): #11     _rootRun (dart:async/zone.dart:1190:13)
E/flutter ( 6263): #12     _CustomZone.run (dart:async/zone.dart:1093:19)
E/flutter ( 6263): #13     _CustomZone.bindCallback.<anonymous closure> (dart:async/zone.dart:1021:23)
E/flutter ( 6263): #14     Timer._createTimer.<anonymous closure> (dart:async-patch/timer_patch.dart:18:15)
E/flutter ( 6263): #15     _Timer._runTimers (dart:isolate-patch/timer_impl.dart:397:19)
E/flutter ( 6263): #16     _Timer._handleMessage (dart:isolate-patch/timer_impl.dart:428:5)
E/flutter ( 6263): #17     _RawReceivePortImpl._handleMessage (dart:isolate-patch/isolate_patch.dart:168:12)
E/flutter ( 6263):

Steps to reproduce

Steps to reproduce the behavior:

1. Create a native ad widget
2. Add the java files to the src folder and add the layout XML file to the res folder.
3. Run app

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Additional context

My code is from the example:

import 'package:flutter/material.dart';
import 'package:google_mobile_ads/google_mobile_ads.dart';

class NativeAdWidget extends StatefulWidget {
  @override
  State<StatefulWidget> createState() => NativeAdState();
}

class NativeAdState extends State<NativeAdWidget> {
  NativeAd _nativeAd;
  final Completer<NativeAd> nativeAdCompleter = Completer<NativeAd>();

  @override
  void initState() {
    super.initState();
    _nativeAd = NativeAd(
      adUnitId: NativeAd.testAdUnitId,
      request: AdRequest(),
      factoryId: 'listTile',
      listener: AdListener(
        onAdLoaded: (Ad ad) {
          print('$NativeAd loaded.');
          nativeAdCompleter.complete(ad as NativeAd);
        },
        onAdFailedToLoad: (Ad ad, LoadAdError error) {
          print('$NativeAd failedToLoad: $error');
          nativeAdCompleter.completeError(null);
        },
        onAdOpened: (Ad ad) => print('$NativeAd onAdOpened.'),
        onAdClosed: (Ad ad) => print('$NativeAd onAdClosed.'),
        onApplicationExit: (Ad ad) => print('$NativeAd onApplicationExit.'),
      ),
    );
    Future<void>.delayed(Duration(seconds: 1), () => _nativeAd?.load());
  }

  @override
  void dispose() {
    super.dispose();
    _nativeAd?.dispose();
    _nativeAd = null;
  }

  @override
  Widget build(BuildContext context) {
    return FutureBuilder<NativeAd>(
      future: nativeAdCompleter.future,
      builder: (BuildContext context, AsyncSnapshot<NativeAd> snapshot) {
        Widget child;

        switch (snapshot.connectionState) {
          case ConnectionState.none:
          case ConnectionState.waiting:
          case ConnectionState.active:
            child = Container();
            break;
          case ConnectionState.done:
            if (snapshot.hasData) {
              child = AdWidget(ad: _nativeAd);
            } else {
              child = Text('Error loading $NativeAd');
            }
        }

        return Container(
          width: 250,
          height: 350,
          child: child,
          color: Colors.blueGrey,
        );
      },
    );
  }
}

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