Hello,
XStore Core is 3.2.11 version on your site, so you need to use 7.2.11 version of the theme.
I’ve provided link to the changelog – https://gyazo.com/8b645b7acb18aa52c66730d57b2c983d
Please update the theme, clear all cache. If any error persists, provide temporary FTP access. If you do not know how to create FTP contact with your hosting provider, they will help you.
Regards