Fatal error: Uncaught Error: Interface 'Symfony\Component\Config\Definition\Builder\NodeParentInterface' not found in /var/www/alldocs/home/rprather/TIWebsite/simplesamlphp_idp/vendor/symfony/config/Definition/Builder/NodeDefinition.php:23 Stack trace: #0 {main} thrown in /var/www/alldocs/home/rprather/TIWebsite/simplesamlphp_idp/vendor/symfony/config/Definition/Builder/NodeDefinition.php on line 23