Gscan error on custom settings option

I have created some custom setting options and used them in the theme.

Gscan showing error for only a particular setting option. I have used that option only in navigation.hbs file.

The error message is as follows:

- Error: A custom theme setting defined in package.json hasn't been used in any theme file.
Files: package.json

I guess Gscan is not checking navigation.hbs file for custom settings options.