Customer Search Page Sql having issues in returning one customer

Hi

We modified Customer Search Page to fetch additional columns but we are facing issues for few customers

if we comment this part of where clause

 and    ps.identifying_address_flag(+) = 'Y'   we can get customer but not sure if this is right option pasting customized sql

select  distinct/*+ INDEX (mpg HZ_MATCHED_PARTIES_GT_U1) */
       hp.party_id,
       hp.party_name,
       hp.party_type,
       fnd1.meaning type_lookup,
       hp.party_number,
       hp.tax_reference,
       hp.jgzz_fiscal_code taxpayer_id,
       hp.duns_number_c duns_number,
       hp.known_as known_as,
       hp.known_as2 known_as2,
       hp.known_as3 known_as3,