I've got the same issue. Logging into the website and the patcher is fine, but using the in-game login I get the 'Invalid Username or Password' (which I have to do since I get either 'server is busy' or 'not allowed' the first time). It's not a case issue, either, since I'm copying it out of my password manager each time. Was working just fine earlier in the day.
Just to follow up, I changed my password and tried again, and got in right away. I didn't have to use the in-game login screen, so not sure if I just got lucky to get in on the first try, but I figured it'd be something you could try.
This has happened to me 3 times (now, just happened again. (Guess who adigregorio is...))
The first two times I just requested a new password, and bam I was back in.
This time, I can't get a response from the password changer (Says "further instructions have been sent", but they are not arriving.) The billing department is quiet too (not even a "thank you we will get to your request" email, probably just busy ATM.
I just want to know if accounts are being hacked? I mean if this keeps up, I am just going to delete this (that) account and use a different (this?) one.
If someone important sees this thread, the account that can actually test the game is "adigregorio". I made this one so I could actually post and ask for some help, maybe my dreams will come true!