Не корректно работает таймер

static async Task Main(string[] args)
    {
            DateTime currentTime = DateTime.Now;
            DateTime desiredTime = new DateTime(currentTime.Year, currentTime.Month, currentTime.Day, hh, mm, ss);
            TimeSpan timeDifference = desiredTime - currentTime;
            if (timeDifference.TotalSeconds < 0)
            {
                desiredTime = desiredTime.AddDays(1);
                timeDifference = desiredTime - DateTime.Now;
            }
            int delayTime = (int)timeDifference.TotalMilliseconds;
 
        Thread.Sleep(delayTime);
            await Task.Delay(delayTime);
            MYfunction();
    }

var cts = new CancellationTokenSource();
var token = cts.Token;
 
await using var reg = token.Register(() =>
{
    Console.WriteLine($"[{DateTime.Now}]: Event triggered");
});
 
var secondSpan = TimeSpan.FromSeconds(1);
cts.CancelAfter(TimeSpan.FromSeconds(10));
while (!token.IsCancellationRequested)
{
    Console.WriteLine($"[{DateTime.Now}]: Waiting...");
    await Task.Delay(secondSpan);
}

static async Task Main(string[] args)
    {
            DateTime currentTime = DateTime.Now;
            DateTime desiredTime = new DateTime(currentTime.Year, currentTime.Month, currentTime.Day, 11, 30, 0);
            TimeSpan timeDifference = desiredTime - currentTime;
            if (timeDifference.TotalSeconds < 0)
            {
                desiredTime = desiredTime.AddDays(1);
                timeDifference = desiredTime - DateTime.Now;
            }
            int delayTime = (int)timeDifference.TotalMilliseconds;
 
            await Task.Delay(delayTime);
            Console.WriteLine("Hello");
    }

var actionTime = DateTime.Now.AddSeconds(10);
 
var timer = new System.Timers.Timer();
var interval = new TimeSpan(0, 0, seconds: 1);
timer.Interval = interval.TotalMicroseconds;
timer.Elapsed += TimerElapsed;
timer.Start();
 
void TimerElapsed(object? sender, System.Timers.ElapsedEventArgs e)
{
    if (actionTime <= DateTime.Now)
    { 
        // Run Action
 
        //optional
        timer.Stop();
    }
}