It has been happening to me for a few days now, but at times i try to start a single player match, nothing happens and the game gets stuck. it's really irritating.
This happens to me on occasion too. Happened last night, and for a straight hour, now. I don't remember what happened the first time, but I had to quit a tutorial stage because it was non-completable, and the moment you click anything that starts a game, you can basically only use chat. I seem to remember reading about this like... a million years ago, and it being an issue with a game you just conceded, won, or disconnected from still going, but being inaccessible. While typing this I just got back in, but all my single player options were gone, and daily skirmish popped up at the bottom of the list.
