No subscription form displaying on subscription page

I created an automatically generated subscription page, but no form appears - only the message "Your current subscriptions are listed here. You can renew, cancel or upgrade your subscriptions by using the forms below."

How do I get the form to appear.

I'm hoping (once I work-out how to get the form to appear) that it links to PayPal.

Where do I find the generated page to edit the content - as when I go into "edit page" there is no content there.