ASP.Net MVC Error: Object reference not set to an instance of an object

hi I use datatable to bind data into table below are codes:

 Getting error object reference not set to an instance of an object.

public DataTable PopulateReseller()
{
    DataTable dt = new DataTable();
    string constr = ConfigurationManager.ConnectionStrings["ConString"].ConnectionString;
    using (SqlConnection con = new SqlConnection(constr))
    {
        string query = "SELECT * FROM Resellers";
        using (SqlCommand cmd = new SqlCommand(query))
        {
            cmd.Connection = con;
            using (SqlDataAdapter sda = new SqlDataAdapter(cmd))
            {
                sda.Fill(dt);
            }
        }
    }
    return dt;
}


public ActionResult List()
{
    var model = new SearchViewModel();
    model.Ostans = PopulateOstan();
    model.Reseller = PopulateReseller();
    return View(model);
}

View Model:

public class SearchViewModel
{
    public Reseller Reseller2 { get; set; }
    public IEnumerable Reseller1 { get; set; }
    public DataTable Reseller { get; set; }
    public List Ostans { get; set; }
    public List Citeies { get; set; }
}