Fatal error: Uncaught Error: Call to undefined function add_action() in /var/www/html/templates/Real-estate/24/inc/upgrade-plus/class-customize.php:39 Stack trace: #0 /var/www/html/templates/Real-estate/24/inc/upgrade-plus/class-customize.php(20): shoppingcart_Customize->setup_actions() #1 /var/www/html/templates/Real-estate/24/inc/upgrade-plus/class-customize.php(88): shoppingcart_Customize::get_instance() #2 {main} thrown in /var/www/html/templates/Real-estate/24/inc/upgrade-plus/class-customize.php on line 39