Regsistration Invalid Code

I had an existing 1.0 account which I used and gained early access to FFXIV ARR. While playing early access, I pre ordered CE for 49.99. I was sent my digital rights code today for the CE however when I enter it on my service account screen under bonus code i get a message that this code is invalid. It wants me to create a new service acount with the digital rights code. I do not want a new account. I want the CE pre order to be applied to my current account. Why is the code invalid?