OneSignal- java.lang.ClassNotFoundException: com.company.NotificationServiceExtension - flutter

Question

dependency : onesignal_flutter: ^3.4.1
Getting error when intialize onesignal service,
i am receiving pushnotifications but when i receive any this will be the log or when i click to open or listen it , this will be the error , please help.
W/SQLiteLog( 8133): (28) double-quoted string literal: "notification"
W/System.err( 8133): java.lang.ClassNotFoundException: com.company.NotificationServiceExtension
W/System.err( 8133): at java.lang.Class.classForName(Native Method)
W/System.err( 8133): at java.lang.Class.forName(Class.java:454)
W/System.err( 8133): at java.lang.Class.forName(Class.java:379)
W/System.err( 8133): at com.onesignal.OSNotificationController.setupNotificationServiceExtension(OSNotificationController.java:190)
W/System.err( 8133): at com.onesignal.OneSignal.init(OneSignal.java:819)
W/System.err( 8133): at com.onesignal.OneSignal.setAppId(OneSignal.java:737)
W/System.err( 8133): at com.onesignal.OneSignal.initWithContext(OneSignal.java:769)
W/System.err( 8133): at com.onesignal.OSNotificationRestoreWorkManager$NotificationRestoreWorker.doWork(OSNotificationRestoreWorkManager.java:64)
W/System.err( 8133): at androidx.work.Worker$1.run(Worker.java:86)
W/System.err( 8133): at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1167)
W/System.err( 8133): at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:641)
W/System.err( 8133): at java.lang.Thread.run(Thread.java:923)
W/System.err( 8133): Caused by: java.lang.ClassNotFoundException: Didn't find class "com.company.NotificationServiceExtension" on path: DexPathList[[zip file "/data/app/~~HoPiaGdWkTctR32PvHQv5w==/com.dukanor-bATfBGE6hTOPr_LqS0AWZw==/base.apk"],nativeLibraryDirectories=[/data/app/~~HoPiaGdWkTctR32PvHQv5w==/com.dukanor-bATfBGE6hTOPr_LqS0AWZw==/lib/arm64, /data/app/~~HoPiaGdWkTctR32PvHQv5w==/com.dukanor-bATfBGE6hTOPr_LqS0AWZw==/base.apk!/lib/arm64-v8a, /system/lib64, /system_ext/lib64]]
W/System.err( 8133): at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:207)
W/System.err( 8133): at java.lang.ClassLoader.loadClass(ClassLoader.java:379)
W/System.err( 8133): at java.lang.ClassLoader.loadClass(ClassLoader.java:312)
W/System.err( 8133): ... 12 more
here is the example i did.
initializeOneSignal([String? newEmail,String? store])async{
await OneSignal.shared.setLogLevel(OSLogLevel.verbose, OSLogLevel.none);
await OneSignal.shared.setAppId("xyz");
await OneSignal.shared.consentGranted(true);
await OneSignal.shared
.promptUserForPushNotificationPermission(fallbackToSettings: true);
await OneSignal.shared.setRequiresUserPrivacyConsent(true);
bool val=await OneSignal.shared.userProvidedPrivacyConsent();
print(val);
await OneSignal.shared.setExternalUserId(store??"" + ";" + newEmail.toString());
OneSignal.shared.setSubscriptionObserver((OSSubscriptionStateChanges changes) {});
OneSignal.shared.setNotificationWillShowInForegroundHandler((OSNotificationReceivedEvent event) {
Get.log('${DateTime.now()} [SignInController.onesingle] ${event.notification.additionalData}');
event.complete(event.notification);
});
OneSignal.shared.setNotificationOpenedHandler(
(OSNotificationOpenedResult result) async {
print('NOTIFICATION OPENED HANDLER CALLED WITH: $result');
print(
"Opened notification: ${result.notification.jsonRepresentation().replaceAll("\\n", "\n")}");
try {
var id = await result.notification.additionalData!["campaignId"];
if(id!=null){
getCampaign(id);
}
Get.log('${DateTime.now()} [SignInController.onesingle] setNotificationOpenedHandler id : $id ');
} catch (e) {
print(e.toString());
}
});
}