Fatal error: Uncaught Error: Call to undefined function add_shortcode() in /home/tholic/training.stjohnkenya.org/wp-content/plugins/paid-memberships-pro/shortcodes/checkout_button.php:28 Stack trace: #0 {main} thrown in /home/tholic/training.stjohnkenya.org/wp-content/plugins/paid-memberships-pro/shortcodes/checkout_button.php on line 28