@wolvesofthemist Try clearing Origin's cache. Maybe the app hasn't updated itself yet.
Or, if you're on a Mac, run the Origin reset tool:
If this doesn't work, you'll need to contact EA customer support to verify that your purchase went through. A support rep should be able to tell you if there's a problem with your credit card—some have been known to deny Origin transactions—or something else blocking your access to the pack.