Unable to print anything in serial monitor when using Unity

[hridwin]

I am using Arduino Uno and Unity 3.4.1, and am trying to communicate them with each other. But the serial monitor is not printing anything. In Unity console i am able to see the logged value "Yes". Here is the arduino IDEs code:

void setup() {
  // put your setup code here, to run once:
Serial.begin(9600);
}

void loop() {
    if (Serial.available()) {
        String receivedData = Serial.readStringUntil('\n');
        Serial.println(receivedData);
    }
    Serial.println("abs");
}

and the output:

And here is the C sharp script for Unity:

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using System.IO.Ports;
using System.Threading;


public class controller8 : MonoBehaviour
{
    // Start is called before the first frame update
    public string portName = "COM3";
    public int baudRate = 9600;
    private SerialPort serialPort;

    void Start()
    {
        serialPort = new SerialPort(portName, baudRate);
        serialPort.Open();

    }
    // Update is called once per frame
    void Update()
    {
        serialPort.WriteLine("Yes");
        Debug.Log("Yes");
    }
    
}

Here is the output:

Edit : Have to clarify that this code works when i close Unity and run it. And also i am able to send data to Unity using serial print, but not receive from Unity.

[sterretje]

You can't use the serial port for multiple applications at the same time. Either you use unity or you use the serial monitor; so close the one that you don't want to use.

//Edit
Your topic has been moved to a more suitable location on the forum. Installation and Troubleshooting is not for problems with (nor for advice on) your project See About the Installation & Troubleshooting category.