Import Demo Install

I purchased this theme and i tried to install it in localhost (Xampp) so i installed it then installed and activated the plugins like this video Exactly but i cant found the import demo in appearance i tried with both themes the parent and the child i also tried this steps ( Tools>Demo Content Install ) but it gives me this note : ( Important: HTTP Loopback Connections are not enabled on this server. If you need to contact your web host, tell them that when PHP tries to connect back to the site at the URL https://localhost:7882/darexchange/wp-admin/admin-ajax.php and it gets the error cURL error 28: Operation timed out after 5005 milliseconds with 0 bytes received. There may be a problem with the server configuration (eg local DNS problems, mod_security, etc) preventing connections from working properly. ) BTW the BACKUP AND DEMO CONTENT INSTALL is activated too after i click install demo content in tools it gives me error in database and the tables incresed and changed. so any help please ?