Authentication context and problem with entity manager

   Hello,
I've got a console application on wich I use the IAuthenticationService to login... I correctly login and it saves the principal but then I call the entitymanager and execute a method I got an exception that the user is not logged in...

in my program.cs I've a configure method that's 

   private void Configure()
        {
            IAuthenticationService authenticationService = IoC.Get<IAuthenticationService>();

            if (authenticationService != null)
            {
                string userName = ConfigurationManager.AppSettings["username"];
                string password = ConfigurationManager.AppSettings["password"];
                myLoginCredential loginCredential = new myLoginCredential(userName, password);

                authenticationService.Login(loginCredential); //here it logs and the AuthenticationContext is ok
            }
        }

When I call my repository 

private bool PopulateSqlData(DateTime data)
       {
           bool isOk = false;

           var sw = new Stopwatch();

           sw.Start();

           try
           {
               repository.GeneratoreReportmyMethod(id, data);
           }
           catch (Exception ex)
           {
               NLog.LogManager.GetLogger("exception").ErrorException("PopulateSqlData", ex);
               return false;
           }

           sw.Stop();
           string str = string.Format("Tempo impiegato per popolare le tabelle dati {0}", sw.Elapsed.ToString());

           NLog.LogManager.GetLogger("generatore").Info(str);
           return isOk;
       }

I get a call to the loginmanager on the server

   public IPrincipal Login(ILoginCredential credential, EntityManager entityManager)
   {
//credential is null here
   }

In my old version using DAF I was calling LinkForAuthentication...what am I doing wrong?
Thanks