cPanel used to give those errors too for certain people. It's probably because your IP address keeps changing. Probably the best solution is to ask your ISP for an IP address that doesn't change constantly, but sometimes they can't do that. If you can't get your IP to stop changing you could try using a VPN or a proxy to login. If there is just a warning, but you don't even get logged out by it then there's really nothing to worry about.
What domains do you want to add?