I guess it would be useful to first determine if this issue is related to the VSCode plugin or a bug in robot framework?
can you try running robot with these same args from outside VSCode and see if you get the same result?
Also it’s probably worth mentioning your robot framework version and the version of the VSCode plugin you are using to run robot (is it a plugin or juts part of VSCode? I don’t use VSCode myself)
Knowing these things will help with troubleshooting,