This happened to me after fighting AI1 and going to PvP1. PvP1 would look like it connected, but I actually started dueling AI1 with a timer. It would naturally time out, but I couldn't do anything since my hand was full of blank, unclickable cards labeled "undefined".
I tried PvP1 again to confirm the bug, and the exact same thing happened. Pretty sure I could've kept going forever. Also pretty sure it's been reported before, though I don't know if not being able to play PvP1 at all is new or not.
PS: upload pics to imgur, open the image so that you have .png or .jpg at the end of the URL, copy the URL and paste it in between the img tags: [img][/img]