SWTOR is experiencing some serious mess with many credit cards not accepted.
http://www.swtor.com/community/showthread.php?t=44374
And, as entering a valid payment method is mandatory EVEN if you have already purchased 30 days of playing time with the game (see http://www.athenpaladins.org/forums/vie ... =90&t=6859 ), this means that people who encounter the credit card issue can't play ATM.
Solution (workaround): use a PayPal account; it works.
Many issues with credit cards not accepted in SWTOR
Re: Many issues with credit cards not accepted in SWTOR
Guess I'm feeling lucky my debit MasterCard worked out.