Do you have the base game? Battlefield 3 Premium does not include the base game Battlefield 3, which is required to play all the extra content that comes with Premium. This is being mentioned at the product details page within the Origin store.
Or, If you're getting the "code already used" message, it means the game code has been registered.
Your game should show up in the "My Games" folder of the Origin account you used to enter the code. If your game isn't there, you're either logged into the wrong account or the game hasn't been activated yet. It can take a while. If it doesn't show up you'll need to contact a Game Advisor.
1 Click on the following link: https://help.ea.com/contact-us
2 Make sure you are logged in (top right corner)
3 Click on the blue button "Contact a Game Advisor"
4 Enter the name of your game or product (or "Origin" for account-related issues) and click "Find Solutions"
5 Select the type of issue and the platform you play on, and click on "Find Solutions".
6 Click on the blue button "I still need help" if the FAQ articles do not apply to your situation.
7 Select a contact option. Note that you may get different contact options depending on your country.
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