How to get response from APNS using C #

I am creating one web api application and I want to send notification to iOS devices.

I tried with pushsharp but it only works fine with a few devices, sending it to multiple devices with expired / invalid tokens without sending notifications for all devices.

So, I proceed with the following code:

public async Task pushMessage(string deviceToken, string message)
{
  int port = 2195;
  String hostname = "gateway.sandbox.push.apple.com";

  String certificatePath = "~/test.p12" // my certificate path 

  X509Certificate2 clientCertificate = new X509Certificate2(System.IO.File.ReadAllBytes(certificatePath), CommonSource.GetAppleCertificatePassword(), X509KeyStorageFlags.MachineKeySet);
  X509Certificate2Collection certificatesCollection = new X509Certificate2Collection(clientCertificate);

  TcpClient client = new TcpClient(hostname, port);
  SslStream sslStream = new SslStream(client.GetStream(), false, new RemoteCertificateValidationCallback(ValidateServerCertificate), null);
   try
  {
     sslStream.AuthenticateAsClient(hostname, certificatesCollection, SslProtocols.Tls, false);
     MemoryStream memoryStream = new MemoryStream();
     BinaryWriter writer = new BinaryWriter(memoryStream);
     writer.Write((byte)0);
     writer.Write((byte)0);
     writer.Write((byte)32);

     writer.Write(HexStringToByteArray(deviceToken.ToUpper()));    
     String payload = message.ToString(); 

     writer.Write((byte)0);
     writer.Write((byte)payload.Length);
     byte[] b1 = System.Text.Encoding.UTF8.GetBytes(payload);
     writer.Write(b1);
     writer.Flush();
     byte[] array = memoryStream.ToArray();
     sslStream.Write(array);
     sslStream.Flush();

     // Read message from the server. 
     //byte[] response = ReadMessage(sslStream);   

     client.Close();
   }
  catch (System.Security.Authentication.AuthenticationException ex)
  {
     LogError(ex.Message);
     client.Close();
  }
  catch (Exception e)
  {
    LogError(e.Message);
    client.Close();
   }            
} 

      

        
        
        
      

    

This code works exactly as I wanted.
But now I want to check the response from the APNS server. So I checked with the byte[] response = ReadMessage(sslStream);

ReadMessage method looks like this:

private byte[] ReadMessage(SslStream sslStream)
{
    MemoryStream ms = new MemoryStream();

    byte[] buffer = new byte[1024];

    int bytes = -1;
    do
    {
        bytes = sslStream.Read(buffer, 0, buffer.Length);

        ms.Write(buffer, 0, bytes);

    } while (bytes != 0);

    return ms.ToArray();
}

      

        
        
        
      

    

But when I run this, it is stuck at bytes = sslStream.Read(buffer, 0, buffer.Length);

I cannot figure out the problem.

Can anyone tell me what is the problem with my code?