Hi,
This forum is for technical support on Blizzard’s Classic (legacy) Games, such as Diablo II (2000).
In-game issues with Activision’s Call of Duty must be reported to Activision Support; see Having Problems with Call of Duty? Read this first! for details.
The issue you are describing does not show up in the Known Issues in Call of Duty: Vanguard, perhaps because it was last updated on 29 July. You may want to report it using the Bug Report form available on that web page.
Good luck !
Edit:
On Twitter on 5 Aug 2022, 4:06 PM
We’ve identified an issue affecting the campaign of
@CallofDuty
Vanguard on PC. The game mode will show up as uninstalled until we can address the issue. We expect to have a fix available by tomorrow.
https://twitter.com/BeenoxCODPC/status/1555646507897987074?t=64GTXbyIZJMj8KqF48jGcw&s=19