WCF pass object from Windows Service to asp.Net application

Question

today I'm trying to pass object with some members via a WCF endpoint I've got two classes :

Person class:

{...}
[DataContract]
public class Person 
{
    [DataMember]
    public string Firstname { get; set; }
    [DataMember]
    public string Lastname { get; set; }
}

Population class:

{...}
[DataContract]
public class Population
{
    [DataMember]
    public string Name { get; set; }
    [DataMember]
    public List<Person> Persons { get; set; }
}

I've got a service like this to serve the endpoint from Windows Service :

{...}
[ServiceContract]
public interface IService
{
    [OperationContract]
    Population GetPopulation();
}

[ServiceBehavior(InstanceContextMode = InstanceContextMode.Single)]
public class Service : IService
{
    public Population GetPopulation()
    {
        List<Person> persons = new List<Person>();
        Person person1 = new Person() { Firstname = "Cameron", Lastname = "Randall" };
        Person person2 = new Person() { Firstname = "Francesca", Lastname = "Horton" };
        persons.Add(person1);
        persons.Add(person2);
        Population population = new Population();
        population.Name = "Name of population";
        population.Persons = persons;
        return population;
    }
}

The endpoint is created like this:

{...}
protected override void OnStart(string[] args)
{
    var address = "net.tcp://localhost:6565/GetElements";
    var uris = new Uri[1];
    uris[0] = new Uri(address);
    IService service = new Service();
    ServiceHost serviceHost = new ServiceHost(service, uris);
    var binding = new NetTcpBinding(SecurityMode.None);
    serviceHost.AddServiceEndpoint(typeof(IService), binding, "");
    serviceHost.Open();
}

I created a console app to test my program, like this :

{...}
internal class Program
{
    static void Main(string[] args)
    {
        try
        {
            Console.WriteLine("Press any key to continue...");
            Console.ReadKey();
            var address = "net.tcp://localhost:6565/GetElements";
            NetTcpBinding binding = new NetTcpBinding(SecurityMode.None);
            var endpoint = new EndpointAddress(address);
            var channel = new ChannelFactory<IService>(binding, endpoint);
            var proxy = channel.CreateChannel();
            var result = proxy?.GetPopulation();
            if (result != null)
                result.Persons.ForEach(p => Console.WriteLine(p.FirstName));
            Console.WriteLine("Press any key to finish.");
            Console.ReadKey();
        }
}

The problem is: When I use the console application, all works fine, but I'm trying to use it from a IIS application in asp.Net and when the response come, the result is a Population object with all members null like this :

Name = null;
Persons = null;

I don't know why... I must do something in my asp.Net application ?

This is the code that I use to query my method :

public void Execute()
{
    var address = "net.tcp://localhost:6565/GetElements";
    NetTcpBinding binding = new NetTcpBinding(SecurityMode.None);
    var endpoint = new EndpointAddress(address);
    var channel = new ChannelFactory<IService>(binding, endpoint);
    var proxy = channel.CreateChannel();
    var result = proxy?.GetPopulation();
    if (result != null)
    {
            result.Persons.ToList<Person>().ForEach(person => Console.WriteLine($"Firstname: {person.Firstname} | Lastname: {person.Lastname}"));
    }
}