shortcode fatal error

Hello there,

I am getting fatal error after using the Frequently bought together shortcode:

Fatal error: Uncaught Error: Call to a member function get_cart() on null in /WEBSITE/wp-content/plugins/woocommerce-boost-sales/frontend/frequently-product.php:925 Stack trace: #0 /WEBSITE/wp-content/plugins/woocommerce-boost-sales/frontend/frequently-product.php(157): VI_WBOOSTSALES_Frontend_Frequently_Product::is_product_in_cart(1724) #1 /WEBSITE/wp-includes/shortcodes.php(356): VI_WBOOSTSALES_Frontend_Frequently_Product->frequently_product_shortcode(Array, ’’, ‘wbs_frequently_…’) #2 [internal function]: do_shortcode_tag(Array) #3 /WEBSITE/wp-includes/shortcodes.php(228): preg_replace_callback(’/\\[(\\[?)(wbs_fr…’, ‘do_shortcode_ta…’, ‘

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