I am attempting to filter an observablecollection by the date saved inside. The user will select the date by using a calender view. 

```
public async Task RefreshItems(bool showActivityIndicator, bool syncItems)
        {
            using (var scope = new ActivityIndicatorScope(syncIndicator, showActivityIndicator))
            {

                var items = manager.GetAppointmentItemsAsync();

                CalendarVM vm = new CalendarVM();
                calendar.SetBinding(Calendar.DateCommandProperty, nameof(vm.DateChosen));
                calendar.SetBinding(Calendar.SelectedDateProperty, nameof(vm.DateSelected));
                calendar.BindingContext = vm;

                var filtered = items.Where(appointmentItem => appointmentItem.Date == SelectedDate);
            }
        }

```

Here is the code from the AppointmentPage class with the user selected date and the data.

```
  public async Task<ObservableCollection<AppointmentItem>> GetAppointmentItemsAsync(bool syncItems = false)
        {

            try
            {

                IEnumerable<AppointmentItem> items = await appointmentTable
                                        .ToEnumerableAsync();

                return new ObservableCollection<AppointmentItem>(items);

            }
            catch (MobileServiceInvalidOperationException msioe)
            {
                Debug.WriteLine(@"Invalid sync operation: {0}", msioe.Message);
            }
            catch (Exception e)
            {
                Debug.WriteLine(@"Sync error: {0}", e.Message);
            }
            return null;

        }

```

and here is the code from the dataManger class to retrieve the data from the database. 

Currently I am getting this error: 

> 
> Error CS1061 'Task>' does not
>  contain a definition for 'Where' and no extension method 'Where'
>  accepting a first argument of type
>  'Task>' could be found (are you
>  missing a using directive or an assembly reference?
> 
> 
>