ORA-28001: The password has expired

Try to connect with the users in SQL Plus, whose password has expired. it will prompt for the new password. Enter the new password and confirm password.

It will work

SQL Plus output image

I have fixed the problem, just need to check:

open_mode from v$database

and then check:

check account_status to get mode information

and then use:

alter user myuser identified by mynewpassword account unlock;

ALTER PROFILE DEFAULT LIMIT PASSWORD_LIFE_TIME UNLIMITED;
alter user EPUSR100 identified by EPUSR100 account unlock;
commit;