Fatal error: Uncaught Error: Class "yii\db\ActiveRecord" not found in /home/cp360482/public_html/yii2/common/models/CurriculumSubjectSectionAllowclassroomtype.php:17 Stack trace: #0 {main} thrown in /home/cp360482/public_html/yii2/common/models/CurriculumSubjectSectionAllowclassroomtype.php on line 17