While performing an import, I faced the below error:

ORA-39097: Data Pump job encountered unexpected error
ORA-39065: unexpected master process exception in DISPATCH
ORA-56935: existing datapump jobs are using a different version of time zone data file

Solution:

Check the value of  DST_UPGRADE_STATE by the following query:

SELECT PROPERTY_NAME, SUBSTR (property_value, 1, 30) value
FROM DATABASE_PROPERTIES
WHERE PROPERTY_NAME LIKE ‘DST_%’
ORDER BY PROPERTY_NAME;

Then try executing the following:

ALTER SESSION SET EVENTS ‘30090 TRACE NAME CONTEXT FOREVER, LEVEL 32’;
exec dbms_dst.unload_secondary;

Re-execute the query:

SELECT PROPERTY_NAME, SUBSTR (property_value, 1, 30) value
FROM DATABASE_PROPERTIES
WHERE PROPERTY_NAME LIKE ‘DST_%’
ORDER BY PROPERTY_NAME;

****check the value of  DST_UPGRADE_STATE should be NONE