Pojedynczy rezultat zapytania

$createdAtCondition = new \DateTime('now -30 days');
        $queryBuilder = $this->createQueryBuilder('cd')
        ->where('cd.createdAt > :createdAt')
        ->andWhere('cd.stepNr = :stepNr')
        ->andWhere("JSON_CONTAINS(cd.serializedData, :pesel, '$.pesel') = 1");

        //$queryBuilder->setParameter('pesel', ".$keyValue.");
        $queryBuilder->setParameter('createdAt', $createdAtCondition);
        $queryBuilder->setParameter('stepNr', $lastStepNumber);
        $queryBuilder->setParameter('pesel', '"'.$keyValue.'"');

        $queryBuilder->orderBy('cd.createdAt', 'DESC')->setMaxResults(1);
        
        return $queryBuilder->getQuery()->getSingleResult();