Having problems opening Incognito Mode in Chrome Browser

I have searched forums for an answer but did not see one…
I am having some issue with configuring Chrome browser to open in Incognito mode

According to documentation I need to go to Project->Settings->Desired Capabilities->Web UI ->Chrome
and them add: args list --incognito

When I try to enter “list” under Type I get an error indicating “An error has occurred. See error log for more details. -1”
When this happend the Type value went back to “String” and Name went to "property.

I did have a resolution value using args and list in Chrome headless that i deleted and then tried to add back but this error is stopping me from adding the value back in.

How do I rectify this issue. How do I access the error log?