I had been unsuccessful at purchasing an account using your regular credit card method, so I decided to select "More purchasing options" and select Discover. At this point, when I click Purchase, it's supposed to redirect me to a Discover web page where I can make the purchase. Unfortunately, It doesn't redirect and instead just tells me:

Error placing order

An error occurred while placing order, please verify credit card info and try again

Well, no order has been placed. I'm supposed to get redirected. I think it might be getting confused by the fact that I HAD entered credit card info previously. However, if I go and clear the entered credit card info, it still doesn't work, so maybe the redirect is just broken.