SQL & PL/SQL :: DBMS_METADATA.GET_DDL Fails With ORA-31603 On Dblink

I have user U1 with dblink DBL1 (private dblink, not public).When I logged in with U1 and try to execute the following statement :

SELECT SYS.DBMS_METADATA.GET_DDL('DB_LINK',OBJECT_NAME)
FROM SYS.USER_OBJECTS
WHERE OBJECT_TYPE = 'DATABASE LINK'
AND OBJECT_NAME = 'DBL1';

I get ORA-31603 error:

ORA-31603: object "DBL1" of type DB_LINK not found in schema "U1"
ORA-06512: at "SYS.DBMS_METADATA", line 4018
ORA-06512: at "SYS.DBMS_METADATA", line 5843
ORA-06512: at line 1

DBL1 script is as follows:

CREATE DATABASE LINK DBL1
CONNECT TO U1 IDENTIFIED BY XX USING 'TNS1';

when I select from user_objects with the following query , it is there.

SELECT *
FROM SYS.USER_OBJECTS
WHERE OBJECT_TYPE = 'DATABASE LINK'
AND OBJECT_NAME = 'DBL1';

DBMS_METADATA.GET_DDL works for every other objects (tables for example) in this schema except for dblinks.