InspecteurPatate On the product page, is that true whether you choose the regular or Gold version of DV? You can click the Gold tab to switch.
For the purchase history, this might be because of the refund, but one other thing you can try is using a different browser, and refreshing the purchase history page if you get the error the first time around. I've seen that error here and there, and it disappears after a refresh or two, although I also haven't received a refund for anything.
As for the "already been used" Amazon code, just get a refund for that. And if the above doesn't work, don't try to buy another copy of DV for now; there may be something stuck on your account, which would in turn be something for EA customer support to solve. But let me know about the above; I can ask around as to whether there's anything else you might do on your end.