Fatal error: Uncaught Error: Class 'AC\Ajax\Handler' not found in C:\xampp\htdocs\wp-content\plugins\admin-columns-pro\admin-columns\classes\Ajax\NullHandler.php:5 Stack trace: #0 {main} thrown in C:\xampp\htdocs\wp-content\plugins\admin-columns-pro\admin-columns\classes\Ajax\NullHandler.php on line 5