Hello Darul Muqarrabin Malaysia,
We would like to know more about your issue in order to provide assistance. We recommend that you perform an import on a fresh WordPress installation. To do this, you can use the WordPress Database Reset plugin (https://wordpress.org/plugins/wordpress-database-reset/). This plugin can be used to remove all existing content and install a new version from scratch.
Please reset the database and provide us with temporary wp-admin access so that we can help you with the import. Please also let us know which demo you would like to import. Do you prefer WPBakery or Elementor?
We look forward to hearing from you.
Best Regards,
8Theme’s Team.