public async Task <HttpResponseMessage> NotAttendedAppointment(Guid appointmenId) { return(await ValidateAndHandleOperationExecutionAsync(async() => { var app = await _calendarDomainService.GetAppointmentsById(appointmenId); app.IsAttended = false; var result = await _calendarDomainService.SaveAppointment(app); return Request.CreateResponse(HttpStatusCode.OK, result); })); }