#simsguide

1.Open the EA-App

2.Navigate to Library and select the game you're having issues with.

3.Click on the Manage Button and select Manage add-ons.

4.A new window should open showing you all the downloadable and installed DLCs. Now simply click the Download Button. If you have multiple DLC you want to install, you have to click Download on every DLC separately. 

That's it, EA should now start to install the DLC.

You can also click the three dots on the right side of the game cover in your library and access manage addons through there.