Fatal error: Uncaught Error: Call to undefined function add_action() in C:\xampp\htdocs\wp-content\plugins\advanced-custom-fields\includes\forms\form-widget.php:36 Stack trace: #0 C:\xampp\htdocs\wp-content\plugins\advanced-custom-fields\includes\forms\form-widget.php(299): acf_form_widget->__construct() #1 {main} thrown in C:\xampp\htdocs\wp-content\plugins\advanced-custom-fields\includes\forms\form-widget.php on line 36