Fatal error: Uncaught Error: Call to undefined function add_action() in /home/ykraanet/public_html/wp-content/plugins/schema-and-structured-data-for-wp/admin_section/newsletter.php:4 Stack trace: #0 /home/ykraanet/public_html/wp-content/plugins/schema-and-structured-data-for-wp/admin_section/newsletter.php(133): saswp_newsletter->__construct() #1 {main} thrown in /home/ykraanet/public_html/wp-content/plugins/schema-and-structured-data-for-wp/admin_section/newsletter.php on line 4