In addition to Washington/Washington DC, I also guessed wrong about which Portland they wanted. They wanted the one in Oregon, not Maine. That was a 50/50 shot, but I was sure "Washington" was not the state since it didn't have DC.

I think they reason they are wrong is because they are looking for cities, not states. Maimi, for example.

Which is also wrong because Washington D.C. is not a city either, even though we all treat it as such.

And there's no obvious place on the site to give them feedback either.