Fatal error: Call to a member function getActiveChildren() on null in /var/www/u0823452/data/www/pkyar.ru/src/AppBundle/Model/AbstractModelCatalog.php on line 722

Fatal error: Uncaught exception 'Symfony\Component\Debug\Exception\FatalErrorException' with message 'Error: Call to a member function getActiveChildren() on null' in /var/www/u0823452/data/www/pkyar.ru/src/AppBundle/Model/AbstractModelCatalog.php:722 Stack trace: #0 {main} Next exception 'RuntimeException' with message 'Failed to start the session because headers have already been sent by "/var/www/u0823452/data/www/pkyar.ru/src/AppBundle/Model/AbstractModelCatalog.php" at line 722.' in /var/www/u0823452/data/www/pkyar.ru/app/cache/prod/classes.php:120 Stack trace: #0 /var/www/u0823452/data/www/pkyar.ru/app/cache/prod/classes.php(498): Symfony\Component\HttpFoundation\Session\Storage\NativeSessionStorage->start() #1 /var/www/u0823452/data/www/pkyar.ru/vendor/symfony/symfony/src/Symfony/Component/Security/Csrf/TokenStorage/SessionTokenStorage.php(78): Symfony\Component\HttpFoundation\Session\Session->start() #2 /var/www/u0823452/data/www/pkyar.ru/vendor/symfony/symfony/src/Symfony/Component/Security/Csrf/CsrfTokenManager in /var/www/u0823452/data/www/pkyar.ru/src/AppBundle/Resources/views/Structure/base.html.twig on line 417