using System;

public class Program

{

    public static void Main() {

        var fechaCierre = new DateTime(2021, 6, 15, 17, 30, 0);

        var fecha = new DateTime(2021, 6, 15, 16, 37,0);

        var horas = (fechaCierre - fecha).TotalHours;

        Console.Write(fecha.AddHours(horas));

    }

}