My colony recently declared independence and I've tried establishing embassies in other colonies using the charter codes of other independent colonies. I get a message that tells the distance to the other colony and how much it will cost to build an embassy there, but when I click "Select Embassy", nothing happens.

My colony info: https://www.my-colony.com/colonies/5XFmvjXx/
I am using the Mac OS X Sierra, version v0.55.0