Symfony içinde the EntityManager is closed hatasını onarma

Doctrine\ORM\ORMException exception "The EntityManager is closed".

public function doSoemthing()
{
    // ....
    $this->em = $this->refreshEntityManager($this->em);
    // ....
}

/**
* @param $em EntityManager
*
* @return EntityManager
*/
private function refreshEntityManager(EntityManager $em)
{
    if (!$em->isOpen()) {
        $em = $em->create($em->getConnection(), $em->getConfiguration());
    }

    return $em;
}