How many decks do you have. Please count them on the website. The game client maxes out at 100 decks.
Ok, to me, you are saying 2 things there. Are you stuck on validating deck in the lobby? Or can you not even get INTO the lobby? Maybe it's just a wording issue. I consider entering the screen as entering the lobby. Inside the lobby we validate the deck before allowing you to queue. And thanks for the information re: Decks. Can you try creating a fresh deck and see what happens? (or if one of the decks is already a new one, then let me know)