Editor Help

I have created a country, and I took a team from Iceland to be in it, but when I go to create the save, it says a team in Iceland Premier Division has no nation set. I have looked through all of the teams in the Iceland Premier Division and all have the right nation and cities set. Can someone tell me how to fix this, as I want to eventually upload it to this site!

Any help is really appreciated!

How did you create a country in the data editor? I wasn't able to make one...