I'll update you here once I have a reply from our second-tier supporters.
Meanwhile, please update WPML and its add-ons on your site and check if the problem persists.
**** Important! Please make a full site backup (files and DB) before you proceed with those steps****
Our second-tier supporter says that we must debug this problem locally. Please allow me to take a copy of your site. I must install a plugin like Duplicator or All In One Migration for this. Please let me know if you agree.
This is a reminder that to get advanced with this issue, our second-tier supporter is still waiting for the code you used to update the original products in English.