How to clear Complaint Item view articles item no and product id and quantity fields in complaint item level based on complaint header level input field ?

Hi Team,

My requirement is  complaint header level Serial is field,if user enter serial automatically header level fields fill automatically, and item level also item 10 article fill automatically.

Now ,if we remove serial field in header level,then automatically data cleared in header level and item level also.but problem is header level fields  cleared properly,but item level item articles not cleared .

in my set method i have written the logic for clearing but it is not working.Could you please suggest how to delete or clearing line items in complaint item view.

Thanks & Regards

Kalpana