WPF DataGrid CellEditEnding column is null

I have a datagrid that contains my observable collection of items. When I want to edit and update my cell in column ModuleType I get an empty column (null) and can't update the values in my collection and get additional errors because it didn't update.

Am I doing something wrong? I am pretty new to C#.

EDIT1: I should add that I bind my collection in code at initialization

XAML DataGrid

<DataGrid x:Name="ModulesTable" 
              Background="#d8deff" 
              Foreground="#383e42" 
              Grid.Row="1" 
              SelectionChanged="ModulesTable_SelectionChanged" 
              CellEditEnding="ModulesTable_CellEditEnding" 
              CanUserAddRows="False"
              CanUserDeleteRows="False"
              CanUserReorderColumns="False"
              AutoGenerateColumns="False">
        <DataGrid.Columns>
            <DataGridTemplateColumn Header="#">
                <DataGridTemplateColumn.CellTemplate>
                    <DataTemplate>
                        <TextBlock Text="{Binding Path=LocalId}"/>
                    </DataTemplate>
                </DataGridTemplateColumn.CellTemplate>
            </DataGridTemplateColumn>
            <DataGridTemplateColumn Header="Module Type">
                <DataGridTemplateColumn.CellTemplate>
                    <DataTemplate>
                        <TextBlock Text="{Binding Path=ModuleTypeName}"/>
                    </DataTemplate>
                </DataGridTemplateColumn.CellTemplate>
                <DataGridTemplateColumn.CellEditingTemplate>
                    <DataTemplate>
                        <ComboBox Text="{Binding Path=ModuleTypeName}" SelectionChanged="ComboBox_SelectionChanged" IsEditable="True">
                            <ComboBoxItem>IZMO</ComboBoxItem>
                            <ComboBoxItem>LIMOAP</ComboBoxItem>
                            <ComboBoxItem>LIMOKO</ComboBoxItem>
                            <ComboBoxItem>VIMO</ComboBoxItem>
                        </ComboBox>
                    </DataTemplate>
                </DataGridTemplateColumn.CellEditingTemplate>
            </DataGridTemplateColumn>
            <DataGridTemplateColumn Header="Clear">
                <DataGridTemplateColumn.CellTemplate>
                    <DataTemplate>
                        <Button>
                            <Image Source="{StaticResource CLOSE}"/>
                        </Button>
                    </DataTemplate>
                </DataGridTemplateColumn.CellTemplate>
            </DataGridTemplateColumn>
        </DataGrid.Columns>

Event Method:

private void ModulesTable_CellEditEnding(object sender, DataGridCellEditEndingEventArgs e)
    {
        Log.Debug("EDITING END");
        if (e.EditAction == DataGridEditAction.Commit)
        {
            Log.Debug("COMMIT");
            var column = e.Column as DataGridBoundColumn;
            Log.Debug("COLUMN: " + column);
            if (null != column)
            {
                Log.Debug("NOT NULL"); // CANNOT GET IN HERE
                var bindingPath = (column.Binding as Binding).Path.Path;
                if (bindingPath == "Col2") 
                {
                    int rowIndex = e.Row.GetIndex();
                    var el = e.EditingElement as ComboBox;
                    Log.Debug("RowIndex: " + rowIndex + ", Type: " + el.Text);
                }
            }
        }
    }

All logs are there just to debug.