Niels van der Velden

Problem:
The client is experiencing an issue where attribute values disappear when editing a WooCommerce product in a secondary language using the WordPress editor. This occurs even if no changes are made to the product and it is simply saved again.
Solution:
We recommend continuing to use the Advanced Translation Editor (ATE) for editing products. The issue arises because the products were initially translated using ATE, and editing them with the WordPress editor can overwrite the ATE translations. To avoid losing translated content, it is best to maintain the use of ATE for all product updates.

If this solution does not resolve your issue, or if it seems outdated or irrelevant to your specific case, please visit our support forum to open a new support ticket. We also highly recommend checking related known issues at https://wpml.org/known-issues/, verifying the version of the permanent fix, and confirming that you have installed the latest versions of themes and plugins.