PLS-00352: Unable to Access another Database 'DB_LINK_NAME'

Hello all,

Please check procedure and suggest how to resolve it?

Procedure:
create or REPLACE PROCEDURE hostname (host_name in varchar2,user_name in VARCHAR2, pass_word in VARCHAR2,table_space in varchar2,pro_file in varchar2)
as
db_link_name varchar2(30);
begin
select db_link into db_link_name from user_db_links where host='''||host_name||''';
dbms_utility.exec_ddl_statement@db_link_name('CREATE USER '||user_name||' IDENTIFIED BY '||pass_word||' DEFAULT TABLESPACE ' ||table_space|| ' PROFILE '|| pro_file|| ' ACCOUNT UNLOCK');
end;
/

Error:

Error(7,1): PLS-00352: Unable to access another database 'DB_LINK_NAME'
Error(7,1): PL/SQL: Statement ignored
Error(7,1): PLS-00201: identifier 'DBMS_UTILITY@DB_LINK_NAME' must be declared

Thanks in advance.