Serial Port does not return any data

Question

I need to write a program that will read the data from the indicator. In the Device Manager on computer the indicator is defined as USB-ITN and create virtual serial port(COM18).

Here is my code:

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.IO.Ports;


namespace SerialPort
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();

            //configuring the serial port
            serialPort1.PortName = "COM18";
            serialPort1.BaudRate = 9600;
            serialPort1.DataBits = 8;
            serialPort1.Parity = Parity.None;
            serialPort1.StopBits = StopBits.One;
            serialPort1.DataReceived += new SerialDataReceivedEventHandler(port_DataReceived);
        }


        private void port_DataReceived(object sender, SerialDataReceivedEventArgs e)
        {
            // Read all the data waiting in the buffer
            string data = serialPort1.ReadExisting();
            rtbTerminal.AppendText(data);
        }


        private void button2_Click(object sender, EventArgs e)
        {
            if (serialPort1.IsOpen)
            {
                serialPort1.Close();
                rtbTerminal.AppendText("Port Closed!\n");
            }
            else
            {
                serialPort1.Open();
                rtbTerminal.AppendText("Port Open!\n");
            }
        }
    }
}

Why I can't to receive data from the indicator after opening the serial port?