Hi there,
That's very unfortuned. This would make me freak out aswell.
What have you tried to slove the problem on your own already?
You can try repair your game like this:
1.) If you haven't already tried, you can go into your Dokuments > Electronic Arts
You should see your Sims 4 folder. You can rename this folder to " Sims 4 old" or whatever you like. This will be your backup for all your saves and mods etc. (EA or The Sims will generate a new folder for you named "Sims 4" later) You can also copy it and save it somewhere save so things wont get lost.
2.) Now you can savely go to your EA App and click the option to: "repair game" (BUT ONLY if you renamed the folder or saved it somewhere save!)
3.) Now. Try to run the game, and see if it looks normal for you now. In this stepp all your Sims should be gone but don't worry, nothing will be lost since we renamed or saved your older sim folder somewhere else.
If your game looks normal to you now, you can exit the game (you dont have to save).
4.) You can now copy from the renamed folder to the new folder: saves, tray, screenshots, recorded videos, music
you can also read following steps here: https://www.patreon.com/posts/60354063 and here https://www.patreon.com/posts/60349367
I hope this will help. If not. Let me know 😇 Good Luck!