Learn how to activate your game on ea-app
1.Go to https://www.ea.com/ea-app
2.Click "Download the EA App"
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3.Once the client is installed and has started, log in with your username / password (create one if needed).
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4.Once logged in, click on your library on the left menu.
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5.Select "Redeem code..."
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6.A window will prompt you to enter the code you purchased on Instant Gaming.
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7.EA will authenticate your code after a few minutes.
8.The game is now visible in your list.
9.Click it to start the download.