Check and Uncheck all CheckBox in WPF DataGrid using C#

I have a Datagrid. In which I have a Checkbox in header. When I clicked on Header checkbox it is selecting/deselecting all records in grid.

<DataGridTemplateColumn.HeaderTemplate>
    <DataTemplate>
        <CheckBox Click="CheckBox_Click" Name="HeaderCheckBox" Uid="HeaderCheckBox" CommandParameter="{Binding}" IsChecked="{Binding Path=DataContext.IsHeaderSelected, RelativeSource={RelativeSource AncestorType={x:Type DataGrid}, Mode=FindAncestor}}"  VerticalAlignment="Center" HorizontalAlignment="Center" />
    </DataTemplate>
</DataGridTemplateColumn.HeaderTemplate>
<DataGridTemplateColumn.CellTemplate>
    <DataTemplate>
        <CheckBox Click="CheckBox_Click" CommandParameter="{Binding}"  IsChecked="{Binding IsSelected}" VerticalAlignment="Center" HorizontalAlignment="Center" />
    </DataTemplate>
</DataGridTemplateColumn.CellTemplate>

But when I click on all individual records HeaderCheckbox is not getting checked. Here is my MVVM model

    public class FineViewModel :  INotifyPropertyChanged
    {
        public decimal TotalAmount { get; set; } = 0;

        public event PropertyChangedEventHandler PropertyChanged;

        private void ReportChange(string propertyName)
        {
            if (null != PropertyChanged)
            {
                PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
            }
        }

        private bool isselected { get; set; } = false;

        public bool IsSelected
        {
            get { return isselected; }
            set { isselected = value; ReportChange("IsSelected"); }
        }

        private bool isactive { get; set; } = false;

        public bool IsActive
        {
            get { return isactive; }
            set { isactive = value; ReportChange("IsActive"); }
        }

        private bool isheaderselected { get; set; } = false;

        public bool IsHeaderSelected
        {
            get { return isheaderselected; }
            set { isheaderselected = value; ReportChange("IsHeaderSelected"); }
        }
    }