Pradeep,

I'm not sure I understand the screenshots and the question. You said the first two columns filter correctly. When I look at your screenshots, I only see two lookup columns. Is that intentional?

This would mean that when you select Product Source, the Items Series is filtered based on that source. Is that correct?

Are you asking if or why the PartNo column does not filter on the Item Series?

Ensure that each one of your columns includes lookup filters to they can bind and filter in a cascading manner.

Thanks Eric. I got this sorted out it was a flaw in the setup. Yes what you assumed is correct the Part Number was not filtering.