GGATE Error 'OCI Error ORA-01407: cannot update ("HRIS"."SYS_CLIENTIDENTIFIER"."SYS_USER_ID") to NULL (status = 1407)'

Transaction can't update table column to NULL

ex:

table name: "HRIS"."SYS_CLIENTIDENTIFIER"
column name: "SYS_USER_ID"

check constraint in "DBA_CONS_COLUMNS" or "ALL_CONS_COLUMNS"

SELECT
CONSTRAINT_NAME, TABLE_NAME, COLUMN_NAME
FROM
DBA_CONS_COLUMNS
WHERE
OWNER LIKE 'HRIS'
AND
TABLE_NAME LIKE 'SYS_CLIENTIDENTIFIER'

CONSTRAINT_NAME                TABLE_NAME                     COLUMN_NAME
------------------------------ ------------------------------ --------------------
FK_SYS_CLIENTIDENTIFIER_USER   SYS_CLIENTIDENTIFIER           SYS_USER_ID <--------------
PK_SYS_CLIENTIDENTIFIER        SYS_CLIENTIDENTIFIER           ID
SYS_C0024107                   SYS_CLIENTIDENTIFIER           TERMINALIP
SYS_C0024106                   SYS_CLIENTIDENTIFIER           CREATEBY
SYS_C0024105                   SYS_CLIENTIDENTIFIER           CREATEDATETIME
SYS_C0024104                   SYS_CLIENTIDENTIFIER           GUID
SYS_C0024103                   SYS_CLIENTIDENTIFIER           ID
SYS_C00241XXX        SYS_CLIENTIDENTIFIER           SYS_USER_ID <--------------

DROP CONFLICT CONSTRAINT

ALTER TABLE "HRIS"."SYS_CLIENTIDENTIFIER" DROP CONSTRAINT SYS_C00241XXX;

and restart GGATE replicat