Fatal error: Uncaught Error: Call to undefined function add_action() in /home/www/act.com.cy/wp-content/plugins/jetpack/modules/related-posts.php:39 Stack trace: #0 /home/www/act.com.cy/wp-content/plugins/jetpack/modules/related-posts.php(28): Jetpack_RelatedPosts_Module->__construct() #1 /home/www/act.com.cy/wp-content/plugins/jetpack/modules/related-posts.php(78): Jetpack_RelatedPosts_Module::instance() #2 {main} thrown in /home/www/act.com.cy/wp-content/plugins/jetpack/modules/related-posts.php on line 39