Missing Pack
@xlissyy First of all, if you're using Origin, please do NOT install the EA App, at least not yet. This problem is easier to fix in Origin than in the App.
Having said that, this problem is also much more common in the App, so you may be using it already. Either way, please clear the cache for the app you're using:
https://help.ea.com/en/help/faq/clear-cache-to-fix-problems-with-your-games/
Restart your computer and repair the game: open your game library, right-click on the Sims 4 icon (Origin) or hover over the Sims 4 icon and click the three dots (EA App), and select Repair. Then try to download Seasons again: in Origin, click the Sims 4 icon, then More > Expansion Packs, find Seasons on the list; in the EA App, click the Sims 4 icon, select Manage > Manage Add-ons, find Seasons, and click Download.
If this doesn't help and you happen to have the Sims 4 CAS Demo installed, please see this thread:
