I have a DataGrid where its ItemsSource bound to a DataTable. When I Update the DataTable, the data from the ViewModel gets updated but the UI won’t. I already use INotifyPropertyChanged for my ViewModel.
Here is my functions

 private DataTable hariKerjaTable;
 public DataTable HariKerjaTable
 {
     get => hariKerjaTable;
     set
     {
         hariKerjaTable = value; 
         OnPropertyChanged(nameof(HariKerjaTable));
     }
 }
 private DataTable kalenderKerjaTable;
 public DataTable KalenderKerjaTable
 {
     get => kalenderKerjaTable;
     set
     {
         kalenderKerjaTable = value;
         OnPropertyChanged(nameof(KalenderKerjaTable));
     }
 }

private async void GetWorkingCalendar()
{
    HariKerjaTable.Clear();
    KalenderKerjaTable.Columns.Clear();
    KalenderKerjaTable.Rows.Clear();

    var data = new
    {
        month = Month,
        year = Year,
    };

    string get = await BaseAPI.PostMethod("calendar/select", JsonConvert.SerializeObject(data));
    if (get is not null)
    {
        JObject jsonObject = JObject.Parse(get);
        JToken dataToken = jsonObject["data"];
        HariKerjaTable = dataToken.ToObject<DataTable>();
    }
    else
    {
        MessageBox.Show("Something wrong when retrieving", "Null", MessageBoxButton.OK, MessageBoxImage.Error);
    }

    Application.Current.Dispatcher.Invoke(() =>
    {
        foreach (DataRow row in HariKerjaTable.Rows)
        {
            DateTime date = DateTime.Parse(row["date_calendar"].ToString());
            Debug.WriteLine(date.ToString("dddndd"));
            if (!KalenderKerjaTable.Columns.Contains(date.ToString("dddndd")))
            {
                KalenderKerjaTable.Columns.Add(date.ToString("dddndd"));
            }
        }
        OnPropertyChanged(nameof(KalenderKerjaTable));
    });

    Debug.WriteLine("+++++++++++++++++++++++++++++++");
    foreach (DataColumn column in KalenderKerjaTable.Columns)
    {
        Debug.WriteLine(column.ColumnName);
    }
}

This is my XAML

<Grid Grid.Row="1" Margin="0,5,0,0">
    <DataGrid ItemsSource="{Binding KalenderKerjaTable, Mode=TwoWay}" FrozenColumnCount="2" AutoGenerateColumns="True"/>
</Grid>

I tried to add Mode=TwoWay and UpdateSourceTrigger=PropertyChanged to the XAML, but it doesn’t change anything.