Winforms TextBox Data binding to Text and Tag (Value and ID) not working

Hi,

 I have a TextBox control which is data bound to Value and ID properties ( Text = Value, Tag = ID) with DataSourceUpdateMode onValidation. Somehow the Model object ID property is updated with null value always. Type of Value is string and Type of ID is Guid?. I am possiblity doing something wrong here. How to make TwoWay mode update possible?

 Regards,

soumya