Missing System Fonts in Illustrator

There is an issue within Illustrator where a specific system font is missing from the MacOS. After a bit of testing, the font is functional in every other adobe software and text applications except for Illustrator. To be more specific, it has the regular font, but not the variables. It happened pretty suddenly and I’ve tried a few troubleshooting options, but I have not found anything as of yet. I would appreciate any help to prevent further problems down the line or at least know how to fix it if it arises again.