Untitled

public async Task<string> TimeOutAsync(string instructorId)
{
    var today = DateTime.Today;

    var timeEntry = (await _firebaseClient
        .Child("TimeEntries")
        .OrderBy("instructorId")
        .EqualTo(instructorId)
        .OnceAsync<TimeEntry>())
        .FirstOrDefault(te => te.Object.TimeIn.Date == today && te.Object.TimeOut == null);

    if (timeEntry == null)
    {
        throw new InvalidOperationException("No active Time In record found for today.");
    }

    var timeOut = DateTime.Now;
    timeEntry.Object.TimeOut = timeOut;
    timeEntry.Object.HoursWorked = timeOut - timeEntry.Object.TimeIn;
    timeEntry.Object.SetFormattedHoursWorked();

    await _firebaseClient.Child("TimeEntries").Child(timeEntry.Key).PutAsync(timeEntry.Object);
    return timeEntry.Key;
}