To Disable/Enable bulk number of users in Oracle Applications, we can use the below API

apps.fnd_user_pkg.EnableUser =>To Enable Users
apps.fnd_user_pkg.DisableUser =>To Disable Users\End Date Users


Syntax:

The below synatx can be used for performing this activity.
We can modify the select statement in Cursor to customize according to need.

declare cursor cur1 is
select user_name from apps.fnd_user where LOWER(user_name) Not IN ('username','username', .......);
begin
for all_user in cur1 loop
apps.fnd_user_pkg.EnableUser(all_user.user_name);
commit;
end loop;
End



DECLARE
   CURSOR cur1
   IS
      SELECT user_name
        FROM fnd_user
       WHERE person_party_id IS NOT NULL;
BEGIN
   FOR all_user IN cur1
   LOOP
      apps.fnd_user_pkg.DisableUser (all_user.user_name);
      COMMIT;
   END LOOP;
END;