Fatal error: Uncaught TypeError: call_user_func_array(): Argument #1 ($callback) must be a valid callback, class App\Controllers\PageController does not have a method "index" in /var/www/html/buying.tw/app/Core/App.php:38 Stack trace: #0 /var/www/html/buying.tw/app/Core/App.php(38): call_user_func_array() #1 /var/www/html/buying.tw/public/index.php(11): App\Core\App->__construct() #2 {main} thrown in /var/www/html/buying.tw/app/Core/App.php on line 38