Setting up Nameservers

Hey when I tried thw post installation on Virtuamin it says my host wasnt found my domain is registed with Resgister how do I set up the dns to have access to it. I am able to put the first nameserver in but when i try vps2 it says its invalid. Thanks for help in advance

We need to know much more about your system and setup to give hints here. For starters, where did you install Virtualmin? What’s the hostname of your server, and where is that zone hosted?