@rileymarie22 It's possible that you have a mod causing this but it's also possible that the furniture CC has become obsolete by a game patch. From what I've seen it's fairly common for this to happen. It's recommended that you check for updates on all of your mods after each game patch release. I'd also check some of the CC tracker sites to see if anything is reported as being obsolete.
Here are a couple of tracking sites I use to check for mod updates and reports of outdated CC.
https://simsonic.weebly.com/modtracker.html
Scroll down to where you see Main Tracker / A - Z and look for your mods there. For many of them listed there you will see update notes and links to sites where you can download current versions.
This site has a good list of CC that was broken by the last game patch. There are also many links to find updated versions of broken CC.
For a quick test you can remove all of your mods to a temporary storage folder on your desktop or an external drive while leaving the CC furniture in your Mods folder. Then delete the localthumbcache.package file from your Sims 4 folder and test everything in a fresh New Game (do not reload any of your old saves while the mods are removed).
If the CC furniture still does not appear in a New Game, then you will know the mods are not causing the issue and that the CC furniture is likely obsolete. For any CC item that is no longer working properly in your game I'd recommend that you remove it from your mods folder right away and research the CC creator's website for updated replacements.
If the CC furniture works fine with all of your mods removed then it is likely that one of your mods needs updating. I would research all of your mods for updates and then try reinstalling the updated versions to your mods folder one or a few at a time while testing in the New Game test save. It's never a good idea to use an outdated mod even if you're not currently seeing any problems in your game. Hopefully once you have replaced all of your mods with updated versions, then all of them will work with your CC furniture and you can go back to playing normally.
@rileymarie22 Whichever the last mod was that you put back in is likely outdated. You can use that mod tracker site to find an update or just search for the mod creator's site. Many mods require updating every time there is a game patch release and many of the mod creators have updates available within a day or two.
