Office 365 Password Never Expire

Office 365 Password Never Expire

Important
Only Office 365 global admins can perform these steps.

In the admin center, go to the Settings > Settings.
Go to the  Security & privacy page. If you aren't an Office 365 global admin, you won't see the Security and privacy option.
Select Password expiration policy.
If you don't want users to have to change passwords, select the checkbox next to Set user passwords to expire after a number of days.
Type how often passwords should expire. Choose a number of days from 14 to 730.
In the second box type when users are notified that their password will expire, and then select Save. Choose a number of days from 1 to 30.
When the user's password expires, they'll get a notification that appears in the lower right corner of their screen.

Reference: https://docs.microsoft.com/en-us/microsoft-365/admin/manage/set-password-expiration-policy?view=o365-worldwide