Issue: If you try sign in via F1 or the Multiplayer menus, XBox live will confirm your sign-in, then once you press "Let's Play" returns you to the main screen as Offline User. Will re-prompt for sign in every time you attempt to enter the multiplayer menu.
Troubleshooting: Drivers, updating xBox app, Win updates, Disabling/adding exceptions to firewall, disabling Defender (only AV) etc.
Resolution: Do not run app as Administrator. Running Grounded as Admin will make XBox sign-in non-persistent (will not remember sign-in status)