Hi @Random and welcome to the community - thanks for posting your issue here
I spoke with one of the guys from the poker team, and it looks like there's a bug when setting up your poker profile.
Can you please try and log in via the browser version? You'll need to create a poker profile the first time you log in (choose alias, avatar, etc.).
You should be able to log in using the poker client, after you've created a profile via the browser version