You can configure the Password expiration in the Password Authenticator
Go to Policy -> Rule Elements -> Authenticators
You will see the Password Expiration field under General -> Local Settings. Enter a very large number (like 9999) which is essentially never expiring (like 27 years)
See the attached Screenshot for details.
Expiration.jpg 165.9 K
AFAIK the maximum is 999 days.
Thanks. I was able to change it.