Fatal error: Uncaught Error: Call to a member function getDescr() on boolean in /var/www/default/sites/elearning/src/Elearning/Controller/TrainingController.php:1477 Stack trace: #0 [internal function]: Elearning\Controller\TrainingController->previewHtmlTrainingAction(Object(Symfony\Component\HttpFoundation\Request), Object(Silex\Application)) #1 /var/www/default/sites/elearning/vendor/symfony/http-kernel/HttpKernel.php(139): call_user_func_array(Array, Array) #2 /var/www/default/sites/elearning/vendor/symfony/http-kernel/HttpKernel.php(62): Symfony\Component\HttpKernel\HttpKernel->handleRaw(Object(Symfony\Component\HttpFoundation\Request), 1) #3 /var/www/default/sites/elearning/vendor/silex/silex/src/Silex/Application.php(586): Symfony\Component\HttpKernel\HttpKernel->handle(Object(Symfony\Component\HttpFoundation\Request), 1, true) #4 /var/www/default/sites/elearning/vendor/silex/silex/src/Silex/Application.php(563): Silex\Application->handle(Object(Symfony\Component\HttpFoundation\Request)) #5 /var/www/default/sites/e in /var/www/default/sites/elearning/src/Elearning/Controller/TrainingController.php on line 1477