Hello,
1/ Do you use the latest version of the browser? Try to clear browser cache.
2/ Theme Options > Speed otpimization > Remove Query Strings From Theme Static Resources > Off. Theme options > General > Mobile Content Optimization > Off. Clear cache and check one more time.
3/ 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.
Let us know results.
Regards