Fatal error: Uncaught Error: Class 'Controller' not found in /var/www/html/dev/sophia_frm_ext_lib/extensions/yiiexcel/example/SiteController.php:3 Stack trace: #0 {main} thrown in /var/www/html/dev/sophia_frm_ext_lib/extensions/yiiexcel/example/SiteController.php on line 3