Sounds like you chose the "will call" option. The confirmation number on the receipt will not get you on the pass holders' website. You have to have either an exchange certificate (aka voucher) in hand or the actual pass. The log on requires the numbers on the back of the pass or voucher.
When you order online, you have to choose the "mail" option (which costs a few dollars more) if you want to access the pass holders' website or order the DDE card by phone.