Are you still having problems?

You need to make sure that the DNS settings on your domain registrar (123reg, 1&1 etc) have an A record pointing to your server’s IP address for the new domain.

Your saying that you can’t access the website using the IP address - this could mean that your DNS changes are still propagating and its trying to take you to the old domain name. Either wait 24-48 hours for the DNS to propagate.

Or add this to your wp-config.php file , below the salts security keys
define(‘WPHOME’,’http://NEWSITE.co.uk’);
define('WPSITEURL’,’http://NEWSITE.co.uk’);
replacing newsite.co.uk with your actual domain name