Seems none of the payment methods on the site are working right now.
Using a CC/DC will forever return “Something went wrong. Please try again.” or will get stuck in a loop where after clicking Pay Now it will redirect back to the Subscribe page.
Using paypal will return that it was successful but the acount with still not have gametime and no charges are shown in either Blizzards payment history or Paypals history.
Have you tried wiping out all the payment info and re-entering it, even if it is the same? If you haven’t tried that, i’d give it a shot, quite often helps.