Fatal error: Uncaught yii\web\HeadersAlreadySentException: Headers already sent in D:\www\wattanapong\vendor\yiisoft\yii2\web\Response.php on line 428. in D:\www\wattanapong\vendor\yiisoft\yii2\web\Response.php:366 Stack trace: #0 D:\www\wattanapong\vendor\yiisoft\yii2\web\Response.php(339): yii\web\Response->sendHeaders() #1 D:\www\wattanapong\vendor\yiisoft\yii2\web\ErrorHandler.php(135): yii\web\Response->send() #2 D:\www\wattanapong\vendor\yiisoft\yii2\base\ErrorHandler.php(262): yii\web\ErrorHandler->renderException(Object(yii\base\ErrorException)) #3 [internal function]: yii\base\ErrorHandler->handleFatalError() #4 {main} thrown in D:\www\wattanapong\vendor\yiisoft\yii2\web\Response.php on line 366