Why Can't Nikto Find My Website?

So I've recently tried to scan Nikto on a website that I have.

I write

nikto -h WebsiteName

(I've removed the website's name on this site. But when i type into Nikto's command line, I put the name there)

Nikto replies in a few minutes with something like

website not found

I know that Nikto works, just don't know why its not working for my website.