I don’t know if anyone has seen your thread yet, or if you’ve managed to resolve the issue on your own, but real quickly I’ll try and be as helpful as I can be.
First, are you on PC or Xbox One? Both versions have a feature where you can play while the game downloads, but generally while the game is downloaded only a limited number of features and characters are playable until the rest of the game finishes downloading. Chances are it may have only had one character completely downloaded at the time you checked.
Also, there are some people having authentication problems sometimes on the PC version. There are one or two community members that may be able to give you assistance on that front.
This thread has someone experiencing a similar issue which may help you resolve your problem:
The community member @GazRJ may be able to help.
If nothing else, ask the developers using the @ symbol and typing developers next to it. The KI team is also on twitter and has helped people with issues with the game using twitter as well.
Hope that helps some, best of luck, hope the issue resolves quickly.