It is advisable to regularly change your password. If your password may have been leaked, it is wise to do a reset immediately.
You can change the password via the admin section Users. To do this, click on the "edit icon" next to the user.
You can create a password yourself, or have a secure password generated through the "Generate" button.
The new password must be equal in both fields. If you then save the user by clicking on "Save" the new password is reset.