For domains that need unlocking, you’ll see the ‘manage domain locking’ option, just click on it.Ok, now click here on ‘unlock domain’, which will allow you to change the nameservers for this domain name.
On most Linux operating systems, the DNS servers that the system uses for name resolution are defined in the /etc/file.
That file should contain at least one line defines a DNS server.
This can be done by selecting the Manage Domain Locking option and clicking on the Unlock domain link.
Once the domain has been unlocked click on the Back to Control Panel link.
Once this is done you should see a message stating that the domain name has been successfully unlocked, and then you can click here to go back to the ‘manage domain’ page. If you wish to change your nameservers to 123 Reg, simply click ‘reset to 123 Reg default’ and it should read ‘ns.123uk’ and in the second box it should read ‘ns2.123uk’.