WPF ListView with Checkboxes unchecks

i have listview with checkboxes. But sometimes, when i check checkbox all others checkboxes checked earlier uncheck, but cant find, where is the problem.

Will be gratefull for any help.

Here is XAML code:

    <ListView ItemsSource="{Binding SeatCars}" SelectionChanged="SeatSelectionChanged">
                <ListView.ItemTemplate>
                    <DataTemplate>
                        <CheckBox Content="{Binding}" IsChecked="{Binding RelativeSource={RelativeSource AncestorType={x:Type ListViewItem}}, Path=IsSelected}"></CheckBox>
                    </DataTemplate>
                </ListView.ItemTemplate>
            </ListView>

Here is EventHandler: But problem persists event without eventhandler.

 private void SeatSelectionChanged(object sender, SelectionChangedEventArgs e)
    {
        foreach (var item in e.AddedItems)
        {
            MainViewModel.SeatSelected.Add(item.ToString());
        }
        foreach (var item in e.RemovedItems)
        {
            MainViewModel.SeatSelected.Remove(item.ToString());
        }
    }