There is a known issue with the Clickbank Pitch Plus integration
If a user has setup an upsell or downsell in the Clickbank Pitch Plus system, when the buyer gets to the download page they will be presented with multiple buttons to get access to the products.
Normally the main product is at the top, and the upsell product below
We have had issues reported that if the top link is clicked, only access to the main product is granted, HOWEVER if the bottom link is clicked (for the upsell/downsell product access) then access to both products is granted
We are looking into a fix for this but for now we advise that users include some notification message in their purchase process so that users will only use the second link - perhaps including "USE THIS LINK" in the product name or download link