Help! MDM item detail iView doesn't save

Hi Gurus,

This is my first post here, please bear my ignorance if the question sounds too beginer level.

Here's my question:

MDM Main table - customer with field "company code"

Sub table - company code

I created an item detail iView in portal with "Create" and "Edit" button. In one of the tabs, I have the company code field which is pointing to the lookup qualified flat multi-valued subtable. So upon creation, the company code is in a table view with "add" button. Click on "add", popup a new window. After giving all values and click on "save", all values lost, the table is still empty.

But under "Edit" mode, I can add entry in company code table by giving values in popup and save it back to main screen.

Does anyone know this is standard feature or there's some setting I am missing?

Hopefully I describe the scenario clearly. And Thanks for all your help in advance.