Fatal error: Uncaught Error: Class "yii\db\Migration" not found in /users/quirl/www/filemanager/spark/protected/runtime/module_backups/calendar_1736926955/migrations/m170717_123220_allow_maybe_decline_flag.php:12 Stack trace: #0 {main} thrown in /users/quirl/www/filemanager/spark/protected/runtime/module_backups/calendar_1736926955/migrations/m170717_123220_allow_maybe_decline_flag.php on line 12