Teams Auto Attendant Calls Not Ringing Agents

Hello Community,

We are facing a recurring issue with our Microsoft Teams Auto Attendant (AA) setup. Incoming calls to our main AA number do not ring the assigned agents' Teams clients. Instead, agents only receive a "Missed Call" notification once the caller disconnects or the AA timeout expires, even though the call never audibly rang on their end.

We are looking for a reliable way to ensure calls are properly routed, audibly ring for agents, and are accurately logged for follow-up.

Environment Details

Platform: Microsoft Teams (Admin Center, New Teams Client)

Licenses: Microsoft 365 E3/E5 for users; Teams Phone Resource Account licenses assigned to AA resource accounts

Routing: Auto Attendant routes directly to a person within the organization

Observed Behavior

A customer calls the Auto Attendant number.

The customer selects an option that routes to a person in the organization.

The customer disconnects while waiting in the AA queue, or the AA timeout is reached.

Agents see a "Missed Call" entry in their Teams activity feed, but no ringing notification or active call alert ever appeared in the Teams client.

Troubleshooting Performed

Microsoft Diagnostics:
The M365 Admin Center diagnostic tool flagged the existing AA resource account as invalid and recommended deletion and recreation.

Recreated Resource Account:
Deleted the old resource account, created a new one, reassigned licenses and phone numbers, and re-linked it to the Auto Attendant.

Despite these steps, the issue persists. We have an open case with Microsoft Support, but we are hoping the community might have additional insights or workarounds for this "ghost missed call" scenario.

Questions for the Community

Has anyone else experienced missed call notifications without the call actually ringing on the agent's Teams client?

Are there any PowerShell configurations, Teams policies, or advanced Teams Phone settings that could be causing or resolving this behavior?