I finally did the PS3 to PS4 upgrade and it's not working. When I launch the game it says "Cannont launch Final Fantasy XIV: A Realm Reborn. Please register the promotion code included with you package or download".

Not only do I not have a promotion code (SE only gave me the voucher code to download it from the PSN which I did) but it also doesn't even say where you'd be putting in this code.

Mog station acknowledge that I've done the upgrade, PSN says that I have fully downloaded the game and updates. What is going on?

A quick google search only shows this was a problem from the beta of the PS4 launch but it is definitely no longer in beta.