I have “no route to host” error when I try to send data to my Arduino.

Arduino hasn’t problems at all. I sent many commands to him with simple code on C# and Python through VS and PyCharm
So he’s ok.

There’s code:

// ViewController.cs

using System;

using AppKit;
using Foundation;

using System.Net.Sockets;
using System.Text;
using System.Threading;

namespace Control
{
    public partial class ViewController : NSViewController
    {
        public ViewController (IntPtr handle) : base (handle)
        {
        }

        public override void ViewDidAppear()
        {
            base.ViewDidAppear();

            this.View.Window.BackgroundColor = NSColor.Black;
            this.View.Window.Title = "Control";
        }

        public override void ViewDidLoad ()
        {
            base.ViewDidLoad ();

            // Do any additional setup after loading the view.

        }

        public void GetRgb(ref int red, ref int green, ref int blue)
        {
            colorPicker.Color.GetRgba(out nfloat r, out nfloat g, out nfloat b, out nfloat a);

            red = (int)(r * 255);
            green = (int)(g * 255);
            blue = (int)(b * 255);
        }

        public void SendData(ref long dateToSend, int r, int g, int b)
        {
            dateToSend = (dateToSend << 8) + BitConverter.GetBytes(b)[0]; // Blue
            dateToSend = (dateToSend << 8) + BitConverter.GetBytes(g)[0]; // Green
            dateToSend = (dateToSend << 8) + BitConverter.GetBytes(r)[0]; // Red

            dateToSend = (dateToSend << 8) + 0x02; // RGB color space
            dateToSend = (dateToSend << 8) + 0x01; // MonoColor mode
            dateToSend = (dateToSend << 8) + 0xa0; // AnimationMode change
        }

        partial void actionButtonSet(NSObject sender)
        {
            int red = 0, green = 0, blue = 0;
            long date = 0;

            GetRgb(ref red, ref green, ref blue); // get RGB colors from NSColorWell
            SendData(ref date, red, green, blue); // saving commands for send

            TcpClient tcpClient = new TcpClient();
            try
            {
                tcpClient.Connect("192.168.1.3", 80);
                NetworkStream stream = tcpClient.GetStream();

                stream.Write(BitConverter.GetBytes(date));
                Thread.Sleep(30);
                tcpClient.Close();
            } finally
            {
                tcpClient.Dispose();
            }
        }

        public override NSObject RepresentedObject {
            get {
                return base.RepresentedObject;
            }
            set {
                base.RepresentedObject = value;
                // Update the view, if already loaded.
            }
        }
    }
}

actionButtonSet is button which should to take color from NSColorWell and to send it to 192.168.1.3:80 IP

I think my app haven’t permission to connect to unit in my private network, but I dunno how to give that permission

pls help me with that, how I can fix that issue

—- Edited —-

My thoughts were right.
I tested simple code in VS and he’s ask for permission.
I give it to him and simple code did it.

Problem is in another now.
How to give permissions to app?