For some reason when I log into my Microsoft Account, Minecraft for some reason every time doesn't notice that I've correctly logged in, or when I get to the main menu it will always say something like "Signing into Microsoft account...", when it won't ever will, and then I can't join any worlds because it wants me to wait for it to sign in, which it won't. This is the pain I go through every day. (Just kidding about that last part.)