couldn’t purchase it as well. when I try using paypal, on clickbank, i press “pay now” and it redirects me to paypal. once i auth and press “pay now” on paypal, i get redirected back to clickbank, but nothing happens, i get into infinite loop of “pay now”s.
I even tried using my bank card to pay, but it tells me “Your payment was declined. Please try another card or attempt to complete your purchase through PayPal”.
I don’t have another card, but i’ve used it to get some other stuff today, so there is definitely something wrong with clickbank 
tried another browser and another computer, still no luck.