Fatal error: Uncaught Error: Class 'yii\db\ActiveRecord' not found in /var/www/html/autocar/vendor/kartik-v/yii2-tree-manager/src/models/Tree.php:49 Stack trace: #0 {main} thrown in /var/www/html/autocar/vendor/kartik-v/yii2-tree-manager/src/models/Tree.php on line 49