Go to your Mods folder and right-click it. If not, you may just need to uninstall the file from your game. Hopefully, they'll get back to you with an updated version of the content or a way to work around the error. "Whenever I place down the couch I downloaded, an error message comes up and says 'script call failed'"). Give them a detailed example of what's happening in the game (i.e. If you've tried all the troubleshooting methods and the mod/custom content still won't work, the best thing to do is contact the original creator and let them know. The only way to fix this would be to buy a copy of The Sims 4 directly from Origin, where you can ensure the game will be patched regularly and compatible with all mods and custom content.
There is no guarantee that they will work with pirated versions of the game, so if you do have a pirated version and a mod isn't working, that could be why.
Usually, the mod's creator will be aware of this and will update his or her website to notify players of this.
With the Sims 4, nearly every time a patch comes out, it breaks a variety of mods.
It won't damage your save game, and this has actually fixed broken CC (particularly issues with script mods) for me in the past. The game will then repair itself and basically do a fresh install of the files needed to run The Sims 4. You can do this by clicking on The Sims 4 in your library, selecting the Settings button, and then clicking on Repair Game (please note that you must not be playing the game when you select this option).