Fatal error: Uncaught Error: Call to undefined function add_action() in /home/helllcom/public_html/wp-content/themes/ro/library/functions/ro_per_product_shipping.php:21 Stack trace: #0 {main} thrown in /home/helllcom/public_html/wp-content/themes/ro/library/functions/ro_per_product_shipping.php on line 21