using System;

using System.Linq;

using Newtonsoft.Json.Linq;

using Microsoft.Graph;

using Microsoft.Graph.Extensions;

using System.Globalization;

public class Program

{

    public static void Main()

    {

        DateTimeTimeZone dt = null;

        dt?.ToDateTime().ToString("dd-MMM-yyyy HH:mm:ss", CultureInfo.CreateSpecificCulture("en-GB"));

    }

}