Fatal error: Uncaught Error: Call to undefined function add_filter() in /var/www/noteswp.new/wp-content/plugins-backup/netbase_solutions/core/modules/one-step-checkout/inc/template.php:34 Stack trace: #0 /var/www/noteswp.new/wp-content/plugins-backup/netbase_solutions/core/modules/one-step-checkout/inc/template.php(20): NBT_OSC_Frontend_Template->__construct() #1 /var/www/noteswp.new/wp-content/plugins-backup/netbase_solutions/core/modules/one-step-checkout/inc/template.php(91): NBT_OSC_Frontend_Template::get_instance() #2 {main} thrown in /var/www/noteswp.new/wp-content/plugins-backup/netbase_solutions/core/modules/one-step-checkout/inc/template.php on line 34