1- The issue could be because of any third-party plugin conflict, 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 a reason for the problem.
And if the issue will still persists then please keep the plugins disabled and let us know here I will debug it deep to find the cause of the issue.
Kindly take a complete backup of your site first.
And I also need your permission to debug your site, which includes deactivating all the third-party plugins and on-site Customization as well.
2- The XStore menu is working fine I have checked it on your site see image: https://postimg.cc/6yKjKyMM there is no issue please check your site after clearing the browser cache I hope you will never face the issue again.
Regards 8Themes Team.
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