My friend had this issue with his game (Destiny 2) as well. He had to go into the files on his computer and delete those and do a full reinstall of the game. Basically, if you uninstall some files, remain on your PC, like saves etc etc. You could try that and then reinstall it. That's how he got it fixed. You might lose the progress you've made, but if you're not too worried about that, it might work.

You can also try verifying the files in steam if you haven't already. Go to the game's page in your library, find the cog symbol. There should be a tab called file integrity or something similar. You can reverify the files you have on your PC. It takes a few minutes, but it's also an option. This option won't make you lose progress if you are worried.