Problem in Adding and Deleting objects

Question

Hi, Using VB Net (2005, Access (2003) in Windows Forms, in my application there are 2 ListBox and a Datagridview. Database and Strong DataSet both have 4 tables and are related; on the dgCurrency_SelectionChanged I do some filtering to supply DataSource for the 2 ListBox, so good so far. My problem start here, upon selecting and element (Item) from left ListBox and adding it to the right ListBox this seem to work (I can see this item has been added to DataBase) but I been trying to delete the item that was selected from the left ListBox, just can do. I been at it for the last 2 weeks, so any help will be greatly appreciated.  Thank you