CCC_AP invoice line level product type and intended use columns to be mandatory based on BU

Hi Team,

We have a business need for Brazil BU that, when we add AP invoice line information, the columns listed below must be required depending on BU (Brazil).

Intended Use
Product Type

We did the required personalization to update the mandatroy field, but it is notworking.
Sand Box Name : BR AP Invoice Form changes

Please let us know if we need to handle things differently or adjust the logic at the Expression Builder level so that we may develop a new sandbox or tweak the code of a current sandbox accordingly.

Note: If it is not possible to mandate the columns, at least we should display a warning message saying the columns (Intended Use, Product type) are mandatory for a specific BU (For this message to appear for only Brazil BU).