Business Partner - Adding Additional Search Criteria

Hi All,

I am trying to add additional search criteria to the Business Partner search screen, but seem to be running into a few issues. On the screen below I would like to add the ability to search on Tax Category and Tax Number.

In MDG >>General Settings >> UI Modeling >> Define Field Properties for UI I de-checked the BP_TAXNUM entity for the BP Data Model (as seen below).

This allowed me to add the Tax Number Category to the search criteria, however there was no Tax Number available (as seen below). Is there a reason why Tax Number is not available?

Also, when I tried to run a search using the Tax Number Category as a criteria, the following error was displayed.

Is the error referring to the query linked to the feeder class (see image below)? If so, how can I update the query to support additional search criteria?

If there is an easier way to add search criteria please let me know. I would really appreciate any help on this.

Thank you,

Peter