Hi,
I have checked this theme on our localhost (WP 5.9 / PHP 7.4 / Theme 1.5.3) and see that the theme works fine.
Could you share the super admin credentials your site? You can click Edit Fields in your first post to add your credentials (website URL & admin login). This info box is private, the info entered there can only be seen by our support staff.
If you can not publish your info, try to check PHP version or disable Layzy load for image.