Fatal error: Uncaught Error: Class 'WPSEO_Date_Helper' not found in /home/customer/www/bmi-calculator.com.au/public_html/wp-content/plugins/wc-multivendor-marketplace/core/class-wcfmmp-store-seo.php:121 Stack trace: #0 /home/customer/www/bmi-calculator.com.au/public_html/wp-includes/class-wp-hook.php(303): WCFMmp_Store_SEO->sitemap_output('') #1 /home/customer/www/bmi-calculator.com.au/public_html/wp-includes/class-wp-hook.php(327): WP_Hook->apply_filters('', Array) #2 /home/customer/www/bmi-calculator.com.au/public_html/wp-includes/plugin.php(470): WP_Hook->do_action(Array) #3 /home/customer/www/bmi-calculator.com.au/public_html/wp-content/plugins/wordpress-seo-premium/inc/sitemaps/class-sitemaps.php(372): do_action('wpseo_do_sitema...') #4 /home/customer/www/bmi-calculator.com.au/public_html/wp-content/plugins/wordpress-seo-premium/inc/sitemaps/class-sitemaps.php(258): WPSEO_Sitemaps->build_sitemap('wcfmmp-stores') #5 /home/customer/www/bmi-calculator.com.au/public_html/wp-includes/class-wp-hook.php(303): WPSEO_Sitemaps in /home/customer/www/bmi-calculator.com.au/public_html/wp-content/plugins/wc-multivendor-marketplace/core/class-wcfmmp-store-seo.php on line 121