im trying to make a shopping cart for a school project and i have the code here. but i get no results
i dont get an error but it just doesnt show anything. the form before this does work with amount but as soon as i want to actually see my shopping cart it wont show

#[Route(‘/shoppingcart/{id}’, name: ‘shoppingcart’)]
public function detail(Request $request, EntityManagerInterface $em, int $id): Response
{
$product = $em->getRepository(Product::class)->find($id);
$form = $this->createFormBuilder()
->add(‘amount’, IntegerType::class, [
‘required’=>true,
‘data’=>1,
‘label’=>’amount’
])
->add(‘add’, SubmitType::class)
->getForm();
$session = $request->getSession();
$form->handleRequest($request);
if($form->isSubmitted() && $form->isValid() ) {

        if(!$session->get('order')) {
            $session->set('order',[]);
        }
        $amount=$form->get('amount')->getData();
       
        $order=$session->get('order');
        $order[]=[$id,$amount];
        $session->set('order',$order);

        $this->addFlash('success','product added!');
        return $this->redirectToRoute('student_category');
    }
    return $this->render('student/detail.html.twig', [
        'product' => $product, 'form' => $form
    ]);
}