I think your NC Soft account log-in name and password are unrelated, and will be different. So you might be using the wrong password for the game.
If you forgot your game password, I think you should be able to use your NC Soft account to reset it.
EDIT: some names *may* have changed. Something about Euro accounts being merged to the NA accounts. Was your account perhaps a Euro account?
No, it is not an EU account. I am just at a total loss. I filed a ticket, just no idea when that will get a reply 
This'll probably fix it:
Login to your NCSoft Master account.
Change the password. (you can change it back, just change it once)
Login to game and you should be fine.
Hello,
I have not played since "freedom" was released. I can log in to my NCSoft master account with no problem. I can't however log in to the game. Did the name you use to log in change or something?
Thanks in advance