No route found for "POST /agent/": Method Not Allowed (Allow: GET)

{% for parking in user.parkings %}

         <table id="file_export" class="table table-striped table-bordered">
                <tbody>
            {% for car in car %}
                <tr>
                <td>
               {{ car.matricule }}
                </td>
                <td>
              <span class="timer" data-expires="{{ car.getExpiresAt() }}">
              </span>

                </td>
             <td>

<button type="button" class="btn btn-dark" href="{{ path('new_amende', {'id': car.id},{'number': car.number}) }}" data-toggle="modal" data-target="#createmodel" data-whatever="{{ car.id }}">
ticket
</button>
            {{render(controller('App\Controller\AgentController:newAmende')) }}

                </td>
                </tr>
             {% endfor %}

/**
     * @Route("/{id}/new", name="new_ticket", methods={"GET","POST"})
     */
    public function newTicket(Request $request, Car $car): Response
    {
        $ticket = new Ticket();
        $form = $this->createForm(TicketType::class, $ticket);
        $form->handleRequest($request);

        if ($form->isSubmitted() && $form->isValid()) {
            $this->addFlash('success','ticket added !');

            $entityManager = $this->getDoctrine()->getManager();
            $entityManager->persist($ticket);
            $entityManager->flush();

            return $this->redirectToRoute('agent');


         }

        return $this->render('Agent/modal.html.twig', [
            'ticket' => $ticket,
            'form' => $form->createView(),
        ]);
    }