Site Problem with Deal of the Day Login?

[o0ovo0o]

I know it's a bit too late, but I've been trying to purchase this deal (http://dealoftheday.redflagdeals.com/deal/national-deals/nanocubejune) so I clicked "Buy Now". It directs me to a site asking me to login with my username and password, which I do. But it won't let me login for some reason. I use the Windows Live Messenger way to login to RFD so I'm wondering whether there is a glitch within the system.

I tried the left hand side registration but it recognizes my username and email too.

Thanks for the help!