Items collection must be empty before using ItemsSource with checkbox control in datagrid wpf

Items collection must be empty before using ItemsSource with checkbox
control in datagrid wpf

This error only occurs when I add this following XAML code :
<DataGridTemplateColumn Header="Ist aktiv" IsReadOnly="True">
<DataGridTemplateColumn.CellTemplate>
<DataTemplate>
<CheckBox IsChecked="{Binding IsActiveBool}" />
</DataTemplate>
</DataGridTemplateColumn.CellTemplate>
</DataGridTemplateColumn>
</DataGrid>