Our engineers are aware of an issue where the SHiFT machine in Concordia may say that the player is not signed into SHiFT while they are signed in. We are investigating possible resolutions and will update this article when more information is available. Please make sure that you wait for SHiFT to finish authentication before pressing "Play" on the title screen.
For update information, please visit:
Xbox 360: https://gearboxsoftware.zendesk.com/entries/57683970-Xbox-360-Update-Hot-Fix-Information
PlayStation 3: https://gearboxsoftware.zendesk.com/entries/57308434-PlayStation-3-Update-Hot-Fix-Information