shortcode not producing link on most products

Hello

using shortcode [yith_wcwl_add_to_wishlist] to display “add to wishlist” link on product page and search archive

link appears on few products, does not show on most. Example list here (appears on 2 out of 11 results)
https://meloman-bg.com/?s=buena+vista&post_type=product
appearance is consistent – the few products it appears on don’t change;
products are typically the same, generated by import via allImport plugin;

Shortcode works here
https://meloman-bg.com/buena-vista-social-club-buena-vista-social-club-2xlp/
Does not work here
https://meloman-bg.com/buena-vista-social-club-at-carnegie-hall-2xlp/

browser inspector shows the following (the part after <!– ADD TO WISHLIST –> is absent where the link does not show)

theme is Flatsome. All up to date

Thank you

<div class=”yith-wcwl-add-to-wishlist add-to-wishlist-142583 wishlist-fragment on-first-load” data-fragment-ref=”142583″ data-fragment-options=”{"base_url":"https:\/\/meloman-bg.com\/buena-vista-social-club-buena-vista-social-club-2xlp?page&name=buena-vista-social-club-buena-vista-social-club-2xlp&product=buena-vista-social-club-buena-vista-social-club-2xlp&post_type=product","wishlist_url":"https:\/\/meloman-bg.com\/wishlist\/","in_default_wishlist":false,"is_single":true,"show_exists":false,"product_id":"142583","parent_product_id":"142583","product_type":"simple","show_view":true,"browse_wishlist_text":"\u0412\u0438\u0436 \u0436\u0435\u043b\u0430\u043d\u0438\u0442\u0435","already_in_wishslist_text":"\u0422\u043e\u0432\u0430 \u0435 \u0432 \u0441\u043f\u0438\u0441\u044a\u043a\u0430 \u0441 \u0436\u0435\u043b\u0430\u043d\u0438\u0442\u0435","product_added_text":"\u0414\u043e\u0431\u0430\u0432\u0435\u043d\u043e \u0432 \u0441\u043f\u0438\u0441\u044a\u043a\u0430 \u0441 \u0436\u0435\u043b\u0430\u043d\u0438\u0442\u0435","heading_icon":"fa-heart","available_multi_wishlist":false,"disable_wishlist":false,"show_count":false,"ajax_loading":false,"loop_position":"shortcode","item":"add_to_wishlist"}”>

<!– ADD TO WISHLIST –>

<div class=”yith-wcwl-add-button”>

<i class=”yith-wcwl-icon fa fa-heart”></i> <span>Добави към желаните</span>

</div>
<!– COUNT TEXT –>

</div>

The page I need help with: [log in to see the link]