grape - table read as a constant

I'm using rails 5 and grape for api, I'm trying to create grape endpoint for the table application.

module GIS::API::V2
  class Applications < ::Grape::API
      get '/' do
        authorize! :read, Application
        status 200
        present Application.list(filter_params, current_user), with: Entities::ApplicationList, only_show: params[:only], person_base: true, current_ability: current_ability, user: current_user, nps_details: params[:nps_details]
      end
  end
end

I'm getting uninitialized constant GIS::API::V2::Applications::Application. I tried changing the class name and file name still the same error occurs.