We are really sorry for the trouble but recently we found the bug in our theme, so soon we will release new update with fixing this issue and we will let you know after we update the theme. We hope you understand.
We check your site and it seems that you have use the Full Width page template, so that’s why it is not showing in your page but we have install another version of the theme where you can get the feature image if you select the Full width page template, so you can check in your site.
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