Solution:
1. Open a sqlplus or Toad session against Stat database and run the insert statement below:
INSERT INTO STAT.STAT_OA_OBJTYPE_MIGR_ORDER (OBJECT_CLASS, OBJECT_TYPE, MIGR_ORDER, DEF_MIGR_ORDER)
SELECT T.OBJECT_CLASS, T.OBJECT_TYPE, 900, 900
FROM STAT.STAT_OBJECT_TYPES T
LEFT JOIN STAT.STAT_OA_OBJTYPE_MIGR_ORDER O
ON T.OBJECT_CLASS = O.OBJECT_CLASS
AND T.OBJECT_TYPE = O.OBJECT_TYPE
WHERE O.OBJECT_CLASS IS NULL
AND O.OBJECT_TYPE IS NULL
AND T.OBJECT_CLASS IN ('L')
AND T.OBJECT_TYPE <> '-1';
COMMIT;
2. Re-start the Oracle Agent.