After creating your Shop in Whiplash, there’s a connection to Whiplash that has to be set up on the eJunkie side as well: http://www.e-junkie.com/ej/help.integration.htm

Here's the important part: "To have order data sent to the same URL for all purchases, you can specify your URL in Seller Admin → Account Preferences as the Common Notification URL.”

The Common Notification URL should be set to: https://www.whiplashmerch.com/platform/ejunkie/order