Direct Routing PSTN calls to Teams Auto Attendant does not forward to Shared Voicemail

Hi all,

I’m running into a strange issue with a Teams Auto Attendant and I’m hoping someone here has seen it before.

We have a Direct Routing number where business hours calls go to a Call Queue, which works, and after hours calls should go to Shared Voicemail for a Microsoft 365 Group. If I call the Auto Attendant from inside our Teams tenant, the after-hours Shared Voicemail works correctly. I can leave a message and the voicemail is delivered to the group inbox as expected.

If I call the same number from the PSTN over Direct Routing, I hear the after-hours greeting, so the schedule and call flow are clearly being hit, but once the greeting finishes I get: “Sorry, we cannot connect your call at the moment, please try again later.”

I have already verified that the resource account has the correct Teams Phone Resource Account license, Enterprise Voice is enabled, the LineURI is assigned, the Online Voice Routing Policy is assigned, the Direct Routing route and SBC look healthy, the Auto Attendant is associated with the correct resource account, the after-hours call flow points to the correct Microsoft 365 Group, and the group mailbox exists and is healthy.

What makes this more confusing is that redirects to internal or tenant-side destinations work, but redirect to Shared Voicemail from a PSTN-originated call does not work. I also tested redirect to an external PSTN number, and that fails with the same error as well.

Because the after-hours greeting plays correctly, and because internal Teams calls can successfully leave voicemail in the shared mailbox, I do not think the issue is with the Auto Attendant configuration itself or with the Microsoft 365 Group mailbox. At this point it looks more like the handoff or redirect path for PSTN-originated calls over Direct Routing is where things break.

Has anyone run into this with a Teams Auto Attendant, Shared Voicemail, and inbound PSTN over Direct Routing? I’m trying to figure out whether this is a known limitation, a bug, or if there is some specific setting related to PSTN-originated redirects that I am missing.

Thanks!