Fatal error: Uncaught Error: Call to undefined function add_action() in /home/worx/public_html/domains/worxgroup.net/public_html/wp-content/plugins/post-smtp/Postman/Postman-Mail-Tester/PostmanEmailTester.php:21 Stack trace: #0 /home/worx/public_html/domains/worxgroup.net/public_html/wp-content/plugins/post-smtp/Postman/Postman-Mail-Tester/PostmanEmailTester.php(34): Postman_Email_Tester->__construct() #1 /home/worx/public_html/domains/worxgroup.net/public_html/wp-content/plugins/post-smtp/Postman/Postman-Mail-Tester/PostmanEmailTester.php(267): Postman_Email_Tester::get_instance() #2 {main} thrown in /home/worx/public_html/domains/worxgroup.net/public_html/wp-content/plugins/post-smtp/Postman/Postman-Mail-Tester/PostmanEmailTester.php on line 21