Hello,
Connect to your site using FTP and downgrade Xstore core plugin version to 1.0.23. Plugin version you can find here https://www.8theme.com/download-plugins/
Don’t update plugin to version 1.1.2 if you use XStore 4.x. 1.1.2 version of Core plugin is not compatible with the old version of theme, only with the 5.0.2 and higher.
Regards
