Fatal error: Uncaught Error: Class "yii\helpers\StringHelper" not found in /mnt/disk1/hosted/cuadro_mando/vendor/yiisoft/yii2-gii/generators/crud/default/controller.php:13 Stack trace: #0 {main} thrown in /mnt/disk1/hosted/cuadro_mando/vendor/yiisoft/yii2-gii/generators/crud/default/controller.php on line 13