gistfile1.txt

public function editAction(Request $request, DeliveryZone $deliveryZone)
{
    $formHandlerResponse = $this->getFormHandlerManager()
        ->createAndHandle(
            $this->get('app.form_handler.delivery_zone_edit'),
            $request,
            [
                'deliveryZone' => $deliveryZone,
            ]
        );
        
    if ($formHandlerResponse->isSuccessful()) {
        return $this->redirectToRoute('app_rambo_delivery_zone_list');
    }

    return $this->render(
        ':rambo/deliveryZones:edit.html.twig',
        [
            'form' => $formHandlerResponse->getForm()->createView(),
            'formHandlerResponse' => $formHandlerResponse
        ]
    );
}