Fatal error: Uncaught Error: Call to undefined function add_action() in C:\xampp\htdocs\wp-content\plugins\wp-timelines\inc\admin\class-timeline-sc-buider.php:5 Stack trace: #0 C:\xampp\htdocs\wp-content\plugins\wp-timelines\inc\admin\class-timeline-sc-buider.php(719): WPEX_TL_SCPosttype->__construct() #1 {main} thrown in C:\xampp\htdocs\wp-content\plugins\wp-timelines\inc\admin\class-timeline-sc-buider.php on line 5