My sim is red on some part of her body. Why is that?

@adoonia90s, are you playing on a console, or on a PC/Mac?  If you are playing on a PC or Mac, do you happen to play with any Mods or Custom Content (CC)? 🤔

If you do play with Mods/CC then please do the following:

1) Move the Mods Folder to your desktop

2) Delete localthumbcache.package file in the game folder.

3) Fix you game in Origin by logging in and go to Library, then right-click on The Sims 4 and choose the "Repair Game" option from the list.  Wait until Origin finishes repairing all your packs and not just the base game.

4) Now, when you turn on your game again, it will create a new mods folder that will be empty.  Check to see if your game is now working without mods/CC.

5) Now you can try adding back items from your Mods folder one at a time checking your game each time to see which item is causing your game to not work properly.  If you have a lot of items, you can try the 50/50 Method. 

The CC creators will usually update the CC items and Mods after these updates, so when you find out which one is the culprit, you can get the updated version from whoever made that item of CC in the first place.  You should try these steps anytime you have problems in your game to rule out CC/Mods problems. 🙂

If the steps listed above don't work or if you don't use Mods or CC then we will have to troubleshoot for another reason your Sim looks like this.

Please reply with your results! 😇