Fatal error: Uncaught exception 'TYPO3\CMS\Extbase\Property\Exception\InvalidSourceException' with message 'The identity property "videoclip" is no UID.' in /usr/share/php5/typo3/typo3_src-7.6.58/typo3/sysext/extbase/Classes/Property/TypeConverter/PersistentObjectConverter.php:219
Stack trace:
#0 /usr/share/php5/typo3/typo3_src-7.6.58/typo3/sysext/extbase/Classes/Property/TypeConverter/PersistentObjectConverter.php(158): TYPO3\CMS\Extbase\Property\TypeConverter\PersistentObjectConverter->fetchObjectFromPersistence('videoclip', 'P77\\P77videos\\D...')
#1 /usr/share/php5/typo3/typo3_src-7.6.58/typo3/sysext/extbase/Classes/Property/PropertyMapper.php(199): TYPO3\CMS\Extbase\Property\TypeConverter\PersistentObjectConverter->convertFrom('videoclip', 'P77\\P77videos\\D...', Array, Object(TYPO3\CMS\Extbase\Mvc\Controller\MvcPropertyMappingConfiguration))
#2 /usr/share/php5/typo3/typo3_src-7.6.58/typo3/sysext/extbase/Classes/Property/PropertyMapper.php(119): TYPO3\CMS\Extbase\Property\PropertyMapper->doMapping('videoclip', 'P77\\ in /usr/share/php5/typo3/typo3_src-7.6.58/typo3/sysext/extbase/Classes/Property/PropertyMapper.php on line 128