You have the ability to configure a password reset policy which forces users to reset their password. You can set the frequency to every 1,2,3,6, or 12 months.
To set a password policy for an existing user, navigate to the Edit User section by clicking your Username -> Settings -> Users.
Click the Edit link next to the user you want to edit.
Scroll down to the Password Policy secton.
Select the desired frequency of the password reset prompts.
Select the Start Date of the reset policy. (In the example below, the password reset prompt will appear 90 days after the 9/12/2018 start date.)
Once set, the password reset prompt will appear for the user when the set time has elapsed. This prompt will appear after the user successfully logs in with their current password.
(Note: To set the password prompt for new users, you will be provided with the same options upon creating the new user.)