mautic: bounces retrieval not working

Error: [Symfony\Component\Debug\Exception\ClassNotFoundException] Attempted to load class "Type" from namespace "Mautic\EmailBundle\MonitoredEmail\Processor\Bounce". Did you forget a "use" statement for e.g. "JMS\Serializer\Annotation\Type", "Doctrine\DBAL\Types\Type", "Aws\DynamoDb\Enum\Type", "Symfony\Component\Validator\Constraints\Type" […]