6/ Could you record a video for a better understanding the problem?
Please try to: WooCommerce > Status > Tools > click on Regenerate the product attributes lookup table.
Please try to disable all the third-party plugins (including cache plugins), that does not come bundled with XStore https://xstore.helpscoutdocs.com/article/36-included-plugins, clear the cache of the browser, and check then. Maybe one of the additional plugins is the reason for the problem.
