I created this code in symfony:
#[Route(‘/buy/{subjectId}’, name: ‘buy_subject’, methods: [‘POST’])]
public function buySubject(Request $request, $subjectId, ManagerRegistry $managerRegistry, $stripeSK): Response
{
$entityManager = $managerRegistry->getManager();
$subject = $entityManager->getRepository(Subject::class)->find($subjectId);

    error_log('Subject ID: ' . $subjectId);

    if (!$subject) {
        throw $this->createNotFoundException('Subject not found');
    }

    dump($subject);

    Stripe::setApiKey($stripeSK);

    error_log('Stripe API Key: ' . $stripeSK);

    $totalAmount = $subject->getSubjectPrice() ;

    error_log('Total Amount: ' . $totalAmount);

    $checkoutSession = Session::create([
        'payment_method_types' => ['card'],
        'line_items' => [[
            'price_data' => [
                'currency' => 'usd',
                'product_data' => [
                    'name' => $subject->getSubjectName(),
                ],
                'unit_amount' => $totalAmount,
            ],
            'quantity' => 1,
        ]],
        'mode' => 'payment',
        'success_url' => $this->generateUrl('subject_success'),
        'cancel_url' => $this->generateUrl('subject_cancel'),  
    ]);


    return $this->redirect($checkoutSession->url, 303);
} 

Only to get this error: [Application] Apr 30 23:52:43 |CRITICA| REQUES Uncaught PHP Exception StripeExceptionInvalidRequestException: “Not a valid URL” at C:UsersuserDownloadsTW2.0-Starter-Project-mainvendorstripestripe-phplibExceptionApiErrorException.php line 38

I expected the click on the Buy button to take me to the stripe checkout page