Pivot Table help!

Pivot Table help!I have created a pivot Table (PT) from a data. The data consists of lots of columns (Fields). One of the fields is Customer Names. The Customer name was created using a data validation list. If I enter a new customer name which is not in the original data list, I would expect the value of that particular customer will not pick as Sum Value even if I refresh the PT. However, I believe I removed the data list by going in to Data validation and clear it. I have also checked the name of the list by going to Names (Names Manager) to see if the list name is still there. Now, when I enter a new customer name, PT still does not pick the new name, but if I change the new name in the old one, PT picks the value. I have rechecked the range by going through the source of the data, but I still could not figure out why a new customer name is not in the PT report.Please help. Anon