Teambuilder D\C problem

I've been having the exact same problem. Whenever I join a TB group, if the game doesn't start quickly enough, I'll DC and it will give the the same "group not found" error message once I've reconnected. Recently this happened to me, but I was still able to chat in the TB team chat with the players on the team. They said that the chat said I left the group even though I could still chat with them.