Hello,
1/ Try to disable all the third-party plugins, that do not come bundled with our theme, and check how it works then.
Do you have this problem when parent XStore theme is activated on the site?
Let us know. If this doesn’t help, provide temporary FTP access.
2/ As I can see, this font-size https://prnt.sc/o24hra comes from WooCommerce Admin plugin.
This one http://prntscr.com/o24i4c from Jetpack plugin.
You need to check settings of these plugins, or contact the support of them.
We are theme author and provide support for the theme, not for the third-party plugins, sorry.
Regards