I was trying to recreate a building from single player mode to multiplayer, I had 2 windows open. At the end I closed multiplayer window first, and now I can't join multiplayer servers. It says "Failed to log in: Invalid Session (Try restarting the game and the launcher)" I already tried to restart the game and the launcher and it didn't work ( I tried few times ). It also can happen randomly. It doesn't show on force quit window but it shows in activity monitor. When you quit it through activity monitor, it resets and works fine, The problem is macOS' "quick-start" thing, where it back-loads to start faster, but some-why it doesn't quit the game actually, that's why transaction key is the same.