Passing data by Navigator.pop(context, value) doesn't work

[sst4tic]

when i try to pass data by Navigator.pop(context, value), and accept it with

Navigator.push( context, CupertinoPageRoute(builder: (context) => ProductScreen(product: productItem))) .then((value)

my value always comes empty. I am using your package.

        ConditionalWillPopScope(
          onWillPop: () {
            print('POP');
            Navigator.pop(context, product);
            return Future.value(true);
          },
        shouldAddCallback: false,