Hello,
The theme is updated on your site, but It is recommended to run import on a fresh WordPress installation. For this you can use WordPress Database Reset plugin https://wordpress.org/plugins/wordpress-database-reset/ The plugin can be used to remove all the existing content and install a new version from scratch. It is recommended to disable the theme https://prnt.sc/unle03 before the reset.
So do reset the current content, install the latest version of the theme (can be downloaded from ThemeForest), and do the import of the mentioned demo, before activations 3rd party plugins.
Regards