Fatal error: Uncaught Error: Interface "Facebook\PersistentData\PersistentDataInterface" not found in /var/www/html/includes/facebook/PersistentData/FacebookMemoryPersistentDataHandler.php:31 Stack trace: #0 {main} thrown in /var/www/html/includes/facebook/PersistentData/FacebookMemoryPersistentDataHandler.php on line 31