Unable to sort in asc order for a custom methods(column) in elasticsearch

module Indexing
    def as_indexed_json(options={})
      self.as_json({
        include: { data: { only: [:some_data] } },
        methods: [:method_one, :method_two, :method_three]
        })
    end
  end

method_two is the string column.

Unable to sort in asc order using method_two column using elasticsearch model but samething works fine in desc order.