Hi,
Nope, it's real. :-)
If you click the link more than once, it may add multiple subscriptions to your cart. Just change the quantity back to 1 and click Update, and then you can checkout and enter the discount code it tells you to. Once you enter the discount code during the checkout process, it'll show you the discounted price. Not sure what happened with the credit card purchase, but maybe just a glitch at that time. Give it another shot, and if you still have problems, feel free to contact support and I'm sure they can get it going.
Thanks,
Russell