Hello Kostas,
Thank you for your response.
Yes, it is a really strange situation.
Please try to do the next, go to Theme Options > Export/Import > export settings in file, then activate XStore child theme (new one 0.0.1), go to Theme Options, and import settings from the parent theme. Check how it works then. Do not forget to clear all cache (from cache plugin, browser, server, and CDN).
Kind Regards,
8theme team
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