Completely unable to log into game, even after a reinstall

I posted about this yesterday, but at the time I assumed it was a server issue. Now 24 hours later, I still can't log in, and no one else seems to be complaining so it must be an issue on my end.

problem is, a full reinstall of the game, including deleting my user data folder, has not helped.

I'm looking for any advice on how I might start troubleshooting this issue because I've never had a game before that's broken only on the client side, but that doesn't get resolved with a fresh install.

EDIT: Update, I had the bright idea to check the game on my laptop, where I get the exact same problem. So this MUST be account related, not machine related.

I've raised a support ticket, because I don't see how I can fix this, but right now I'm considering just requesting a refund since I'm unable to play a game I paid for.