Creating a folder on android device internal storage does not working

Question

For some reason i canot create a folder with a file on the internal storage. Even with the latest avaiable permission manager where i granted permission, it does not working. I read an articel (Android 13 - READ_EXTERNAL_STORAGE_PERMISSION still usable) that there is no need for asking permission if targetSdkVersion 33 is set?

compileSdkVersion 33 minSdkVersion 20 targetSdkVersion 33

Ive set the permission in Android Manifest:

android:requestLegacyExternalStorage="true"

This is my code:

Future saveQrCode({String? qrCode})async{
  if(Platform.isIOS){
     final Directory appDocDir = await getApplicationDocumentsDirectory();
     final Directory appDocDirFolder =  Directory('${appDocDir.path}/account/');
    if ((!await appDocDirFolder.exists())) {
      appDocDirFolder.create();
      final File file = File('${appDocDirFolder.path}/qrCodeGenerated.txt');
      await file.writeAsString(qrCode!);
    }
  }else{
     final Directory? appDocDir = await getExternalStorageDirectory();
     final Directory appDocDirFolder =  Directory('${appDocDir?.path}/account/');
    if ((!await appDocDirFolder.exists())) {
      appDocDirFolder.create();
      final File file = File('${appDocDirFolder.path}/qrCodeGenerated.txt');
      await file.writeAsString(qrCode!);
    }
  }

} 

On Ios everything works fine, only android shows no effect at all Does anyone have an idea? If you need more information, let me know! Thank you