January 2023 - last edited January 2023
I had this issue, went 3 days and a couple of hours trying to fix this, Now this is only if you bought the CD.
I bought my cd/ expansion pack off of Amazon, after hours of reaching out to the ea app, the last person I talked to said to, call what ever store you got the CD from, and ask for a refund, I did and and I got my 20 bucks back and was able to get a new Sims 3 Expansion pack. I hope this helps! =p
January 2023
@AaylahF96 Open the EA app. Log in - this should connect the EA app to your EA account. click my collection and to the upper right of the installer games you should see a button + REDEEM CODE. Enter the code and click next. When you are done with the code click the Sims 4 game icon - click manage - click manage add-ons. If everything went right you should the new pack on top with a download button. click the download button. If the pack is available for download you shouod see the pack download in the lower left of the EA app. If everything went right the game should be ready to play with the new content.