not passing values

Question

i was trying to create a simple service for login. but the value is not getting in respository class. i think i miss some code..can anyone help me ..? thanks in advance.

here is my code for controller

static LoginRespository repository = new LoginRespository();

        public string AddEmployees(Login Emp)
        {
            var response = repository.AddEmployees(Emp);
            return response;

        }

and respository class here

public string AddEmployees(Login Emp)
       {

           SqlCommand com;
           SqlConnection con = new SqlConnection(@"Data Source=DOTNET;Initial Catalog=edin;Integrated Security=True;Pooling=False");
           try
           {
               com = new SqlCommand("select * from data where name='" + Emp.username + "'", con);
               con.Open();
               SqlDataReader dr = com.ExecuteReader();
               if (dr.HasRows)
               {
                   return "success";
               }
               else
               {
                   return "error";
               }
               con.Close();
           }
           catch (Exception aa)
           {
               return aa.ToString();
           }
       }

and my model class

public string username { get; set; }
public string password { get; set; }

 can anyone tell what mistake i have made..