not all of my cc shows up in game! how do i fix this?

so, i downloaded some mm custom content (i recently switched to maxis match), and everything worked fine, but when i downloaded some more, only a couple of the items i downloaded showed up in game. i then proceeded to delete a bunch of my old cc and almost all of the new cc i downloaded, hoping it was an issue with one of the files i'd downloaded, but it didnt work. i hardly have any cc anymore and when i try and download cc, about half the items i download don't show up. does anyone know how to fix this?