I can verify that you cannot make peace with Alex (I think there was a typo in your post) and that you can't DoW any of the other civs. You probably configured the game for "Always Peace." This does appear to be a bug, but it's not certain that Firaxis/2K Games will fix it. The "Always Peace" option isn't available by default and probably will be disabled for you by the next patch or if you verify the game cache. Still, we can leave your post here in case someone takes an interest in this issue. Thanks for the report.