I just received an e-mail back from Amazon stating that Pampers are no longer available under the S&S program. If you still have a subscription, they will honor it. DO NOT cancel your subscription unless you don't need the product. I made that mistake and they are not able to reactivate it. You can make a size change to your subscription under 'Your Account'.
We got the same error message so we contacted Amazon and they put in a ticket to their tech support group. As of today it seems to be working again - I just went and changed the size on my existing subscription, so I recommend you give it another try.
I'm wondering the same thing. I subscribed for the wipes about a week ago and came back now to find that the option is no longer available on Pampers products. It appears that my subscription to the wipes is still intact though.