Organizing and accessing contact information in Outlook.com
Hello Sue,
I'm Diane, an Office Apps & Services MVP specializing in Outlook, and I’m happy to help you today.
It's a temperory problems with groups -
https://portal.office.com/ServiceStatus
Title: Users may be unable to send email to Outlook.com groups
User Impact: Users may be unable to send email to Outlook.com groups.
More info: Users that encounter this problem receive an error stating there was a delivery failure to the recipient.
Current status: We're reviewing available service telemetry and user-provided data to assess the cause of this problem and how we'll resolve it.
Next update by: Monday, June 27, 2022, at 6:30 PM UTC