Fulfillment Email is the email address where notifications about points, rewards, and redemptions will be sent. It can be any valid email address and does not need to belong to a registered member of your community.

Administrative Notifications settings allow you to control when and how you receive important alerts. The email address used for administrative notifications must be registered as a member of your community.

Refer to this helpfile: https://www.questionpro.com/help/communities/communities-administrative-notifications.html