one to one relationship issue

I have two tables with one to one relationship as shown below where table 1 is direct query in actual table and 2 is import. In the table visual it is not displaying the rows for 5 and 6 (both reference and product id). As soon as I add the product ID from table 2  reference 5 and 6 rows goes missing. I checked the show items with no data but it is not working correctly.

Note : In the example table above it works fine but not in my actual scenario.