Heavensward CD issues

So I bought the phsycial version of Heavensward but when I tried to instal it I got a message that was this
http://i.imgur.com/lhdBgRp.png
The thing is that I have the steam version of FF14 and I tried to use the code on both Mogstation and steam and neither worked.
What do I do?

If you've got the Steam main game then you need to also buy the expansion on Steam. There's no workaround for this sorry.

All you can really do is try and get a refund and buy it again on Steam.

Sorry I don't have better news!