It seems you are in the System Library in spite of User Library.
Please follow the below steps to navigate to the location.
> Open Finder
> Click on Go Menu > Go To Finder
> Type in ~/Library/Preferences
> Rename com.adobe.Lightroom5.plist to old.com.adobe.Lightroom5.plist (For Lightroom 5)
Rename com.adobe.Lightroom6.plist to old.com.adobe.Lightroom6.plist (For Lightroom 6)
> Restart Lightroom and check
Let me know if this helps
It worked! genius.
Glad to hear that the issue is resolved.