dbi_link help

Hi,
Im new to dbi_link. I had installed dbi_link and run the dbi_link.sql script . This is the script that I ran after that and it didn't have any errors.  Now the schemas dbi_link and EMPLOYEE are created in my postgres database. The user is "postgres" in both the databases with the same password in both.

UPDATE
    pg_catalog.pg_settings
SET
    setting =
        CASE WHEN 'dbi_link' = ANY(string_to_array(setting, ','))
        THEN setting
        ELSE 'dbi_link,' || setting
        END
WHERE
    name = 'search_path'
;

SELECT make_accessor_functions(
    'dbi:Oracle:database=postgres;host=...;sid=....;port=1521',
    'postgres',
    'postgres',
    '---
AutoCommit: 1
RaiseError: 1
',
    NULL,
NULL,
     NULL,
    'employee'

);

When I try to insert into or select from the oracle database I get this error...

ERROR:  error from Perl function "remote_select": error from Perl function "cache_connection": DBI connect('database=postgres;host=...;sid=...;port=1521','postgres',...) failed: ERROR OCIEnvNlsCreate. Check ORACLE_HOME (Linux) env var  or PATH (Windows) and or NLS settings, permissions, etc. at line 137 at line 13.

Im not sure what this error is. I had set my ORACLE_HOME, NLS settings etc. Is there anything else that needs to be done ?

Thanks
Sharmila