Flutter Navigation shows a black 404 screen when going back from a page - flutter

Question

I'm facing this issue with Navigator in Flutter where when I go back from a page I get redirected to a black 404 page.
This is the navigation flow:
Login screen
HomePage screen
After being logged in, I am redirected to the Homepage and I shouldn't be able to go back to a previous screen, but if I swipe to the right I'm shown a black page with a 404 label and I can't move from there. Thank you in advance for any help!
Here I provide some code:
class SignInPage extends StatelessWidget {
static const routeName = '/signIn';
const SignInPage({Key? key}) : super(key: key);
#override
Widget build(BuildContext context) {
return Scaffold(
body: Column(
children: [
Expanded(
child: Stack(
children: [
const Positioned(
left: -20,
top: -20,
child: AnimatedCircle(color: AppColors.lightBlue),
),
const Positioned(
right: -50, top: 150, child: AnimatedCircle(color: AppColors.lightOrange)),
const Positioned(
bottom: 60, left: -70, child: AnimatedCircle(color: AppColors.lightGreen)),
const Positioned(
right: -50, bottom: -60, child: AnimatedCircle(color: AppColors.lightRed)),
Column(
mainAxisAlignment: MainAxisAlignment.center,
children: [
Image.asset('assets/images/logo.png'),
Container(
width: MediaQuery.of(context).size.width * 8,
margin: const EdgeInsets.symmetric(horizontal: Dimens.SPACING_XL),
child: StyledButton.outlined(
title: 'Sign in with Google',
leading: Image.asset('assets/images/google.png', scale: 30),
onPressed: () async {
final res = await Authentication.signInWithGoogle();
await Authentication.userSetup(res.user!);
Navigator.of(context).popAndPushNamed(HomePage.routeName);
},
),
),
],
),
],
),
),
],
),
);
}
}
class HomePage extends StatelessWidget {
static const routeName = '/homepage';
static const _padding = EdgeInsets.symmetric(horizontal: 20.0, vertical: 6.0);
static const _dividerOptions = 30.0;
const HomePage({Key? key}) : super(key: key);
#override
Widget build(BuildContext context) {
return ChangeNotifierProvider(
create: (_) => ItemsProvider(),
child: Consumer<ItemsProvider>(
builder: (_, provider, __) => Scaffold(
resizeToAvoidBottomInset: false,
appBar: AppBar(
automaticallyImplyLeading: false,
actions: [
IconButton(
onPressed: () => Navigator.of(context).pushNamed('/user'),
icon: const Icon(Icons.person)),
],
),
floatingActionButton: Visibility(
visible: provider.buttonVisibility,
child: FloatingActionButton(
heroTag: "btn1",
backgroundColor: AppColors.red,
child: const Icon(Icons.add, color: AppColors.splashColor),
onPressed: () {
showModalBottomSheet(
context: context,
isScrollControlled: true,
builder: (context) => buildModal(context, provider),
);
}),
),
body: Padding(
padding: _padding,
child: Column(
children: [
TopCard(
itemCount: provider.itemsCount,
onPressed: () {
provider.deleteAllItem();
Navigator.of(context).pop();
},
),
const Divider(
height: _dividerOptions,
thickness: 1.0,
indent: _dividerOptions,
endIndent: _dividerOptions,
),
const Expanded(
child: ItemsList(),
),
],
),
),
),
),
);
}
SingleChildScrollView buildModal(
BuildContext context,
ItemsProvider provider,
) {
return SingleChildScrollView(
padding: EdgeInsets.only(bottom: MediaQuery.of(context).viewInsets.bottom),
child: Container(
decoration: const BoxDecoration(),
child: AddItemScreen(args: AddItemScreenArguments(provider.addItem)),
),
);
}
}