def answer
      if trx = LolitaFirstData::Transaction.where(transaction_id: params[:trans_id]).first
        response = gateway.result(params[:trans_id], client_ip_addr: request.remote_ip)
        trx.process_result(response)
        redirect_to trx.return_path
      else
        render text: I18n.t('fd.wrong_request'), status: 400
      end
    ensure
      if trx
        LolitaFirstData.logger.info("[#{session_id}][#{trx.paymentable_id}][answer] #{response}")
      end
    end
def answer
      if trx = LolitaFirstData::Transaction.where(transaction_id: params[:trans_id]).first
        response = gateway.result(params[:trans_id], client_ip_addr: request.remote_ip)
        trx.process_result(response)
        redirect_to trx.return_path
      else
        render text: I18n.t('fd.wrong_request'), status: 400
      end
    ensure
      if trx
        LolitaFirstData.logger.info("[#{session_id}][#{trx.paymentable_id}][answer] #{response}")
      end
    end
there we land after returning from FirstData server
 then we get transactions result and redirect to your given "finish" path