Error with complex Oracle query

$this->db->select("pu.username,
      pu.last_name,
      pu.first_name,
      pu.middle_name,
      ppi.passport_number,
      ps.passport_status_desc,
      pmax_status_date
    FROM  
      passport_users pu,
         (select pi.username,
                 pi.passport_number,
                 max(pid.passport_status_date) pmax_status_date
          from passport_information pi,
               passport_information_detail pid    
          where pi.username = pid.username
          group by pi.username,
                   pi.passport_number) p_max_status,
       passport_information ppi,
       passport_information_detail ppid,
       passport_status ps
    WHERE pu.username = p_max_status.username
       and pu.username = ppi.username
       and ppi.passport_number = p_max_status.passport_number
       and ppi.passport_number = ppid.passport_number
       and ppid.passport_status_date = p_max_status.pmax_status_date
       and ppid.passport_status = ps.passport_status
       and sysdate between ppi.passport_issue_date and NVL(ppi.passport_expiration_date, sysdate)", FALSE);

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I don't think it is embedded...