Hello @Marek,
Thanks for the video, but we are unable to help without the ability to check the situation on your site more deeply. Because of this we 2 times ask you about temporary wp-admin access. Please provide mentioned access, you will be able to delete that account once the problem will be solved.
Before this, please do next tests:
1/ 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.
2/ How does it work when the default WC theme – Storefront is activated on your site?
It is important to check if the problem persists with the default theme to find out if it comes from the theme or from something else. Go to Appearance > Themes > install and activate the Storefront theme.
Widgets could be messed up after switching, so open the Appearance > Widgets tab before switching to be able to move the widgets to the correct area after switching back.
Regards
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