OIT has confirmed a service issue with Office 365.
Management of Distribution Group membership is currently unavailable in Outlook on the Web (OWA). This does not affect mail to and from distribution groups.
OIT staff are working with the vendor to restore service, but there is no estimated time to resolution.
If you have questions about this outage or would like to report additional service impacts please contact the OIT Service Desk: https://oit.duke.edu/help