Fatal error: Uncaught InvalidArgumentException: Routing requirement for "slug" cannot be empty. in /var/www/vhosts/libreriale.es/httpdocs/vendor/symfony/routing/Route.php:553 Stack trace: #0 /var/www/vhosts/libreriale.es/httpdocs/vendor/symfony/routing/Route.php(443): Symfony\Component\Routing\Route->sanitizeRequirement('slug', '') #1 /var/www/vhosts/libreriale.es/httpdocs/vendor/symfony/routing/Route.php(428): Symfony\Component\Routing\Route->addRequirements(Array) #2 /var/www/vhosts/libreriale.es/httpdocs/vendor/symfony/routing/Route.php(57): Symfony\Component\Routing\Route->setRequirements(Array) #3 /var/www/vhosts/libreriale.es/httpdocs/es/router.php(42): Symfony\Component\Routing\Route->__construct('/especial/{slug...', Array, Array) #4 /var/www/vhosts/libreriale.es/httpdocs/vendor/symfony/routing/Loader/ClosureLoader.php(36): {closure}() #5 /var/www/vhosts/libreriale.es/httpdocs/vendor/symfony/routing/Router.php(198): Symfony\Component\Routing\Loader\ClosureLoader->load(Object(Closure), NULL) #6 /var/www/vhosts/libr in /var/www/vhosts/libreriale.es/httpdocs/vendor/symfony/routing/Route.php on line 553