Unable to Redeem Early Access Code

Been having this problem for a while now... I pre-ordered Heavensward from my local Gamestop, got the 6-3-6-3 code, and entered it into the instructed site. However, when I go to enter my early access 20-digit code, it keeps saying that it is invalid and doesn't let me proceed, even though I made no mistakes. What's worse, the Mog Station doesn't even realize that I HAVE entered a code, as I don't even have the line of text in my account info that says when I do. What gives? Did I do something wrong?

Extra Info:
- I'm on PC
- I downloaded ARR through Steam
- I've used my back-up code and got another 20-digit code. That one doesn't work either.

I had this problem, too, though I bought from the official Square-Enix Online Shop. I kept getting invalid code when trying to put it in on the Mog Station. It turns out that because my account is a Steam account, the only game code version you can use for a Steam account must be bought directly from Steam. :( That's what the SE customer service reps told me in the live chat yesterday.

I had to get a refund on the game I bought, and rebuy it from Steam. But Steam's site wouldn't let me buy the expansion because it said I had never played the FFXIV base game through them.. apparently you can get that part resolved if you join the live chat through customer support on the FFXIV/Square-Enix site customer support section, but as the live chat customer service had closed for the night yesterday, a friend bought the base game for me on Steam just so I could go ahead with buying the expansion there. :(

The good news is, the Heavensward I bought from Steam worked just fine when putting in it's code on Mog Station! :D It was a huge headache to figure all that out, though, I admit. ;_;

Here's the directions I followed on the front page to get to the correct live chat for help: http://na.finalfantasyxiv.com/lodest...c83e7fec89b4b3

That worked like a charm Asheran, thank you so much! Now the real challenge starts... getting my money back from GameStop :0