Teams meeting attendees are stuck in the "lobby" and host has joined by phone and is not prompted to admit

The organizer should authenticate as the meeting organizer with their Audio Conferencing PIN when dialing in; after the meeting starts, press *21 to admit everyone still waiting in the lobby.

Organizer steps when joining by phone

1. Dial the conference number and enter the meeting’s conference ID.
2. When prompted, indicate that you are the meeting organizer.
3. Enter the organizer’s Audio Conferencing PIN. The PIN—not the conference ID—authenticates the caller as the organizer and starts the meeting when no Teams app user has already started it.^1^
4. Press *24 to hear how many participants are waiting in the lobby.
5. Press *21 to admit all waiting participants. Teams does not provide individual lobby admission through the telephone interface; *21 admits everyone.^1^

Merely entering the conference ID can join the organizer as an ordinary caller. The PIN is what identifies the caller as the organizer and starts the meeting over the phone.^2^

Why “Everyone” may not be sufficient

Even with Who can bypass the lobby? → Everyone, participants who are anonymous, from an untrusted organization, or dialing in can remain in the lobby until a verified participant joins. Microsoft documents that this behavior depends on the organizer’s meeting policy.^3^

For a scheduled meeting, verify these options beforehand:

1. Open Teams → Calendar.
2. Select the meeting → View event → Options.
3. Under Meeting access:
   • Set Who can bypass the lobby? to Everyone.
   • Turn on People dialing in can bypass the lobby.
   • Select an appropriate value under Who can admit from the lobby.
4. Select Apply.^3^

The second toggle primarily controls phone callers; it does not replace the organizer’s PIN authentication when the organizer must start the meeting by phone.

If the organizer does not know the PIN

The organizer can reset it at the Teams Audio Conferencing PIN reset page. Alternatively, an administrator can use:

Teams admin center → Users → select the organizer → Edit → Audio Conferencing → Reset PIN → Reset

After resetting it, use the new PIN when the telephone prompt asks the caller to authenticate as organizer.^4^

Administrator fallback

If the organizer authenticates with the PIN but app attendees still remain blocked, the Teams administrator should inspect the policy assigned to that organizer:

1. Go to Teams admin center → Meetings → Meeting policies.
2. Open the organizer’s assigned policy.
3. Under Meeting join & lobby, review:
   • Anonymous users can join a meeting
   • Anonymous users and dial-in callers can start a meeting
   • Who can bypass the lobby
   • People dialing in can bypass the lobby
   • Who can admit from lobby
4. Save any changes; policy changes can take up to 24 hours.^5^

Enabling Anonymous users and dial-in callers can start a meeting permits a leaderless meeting when bypass is set to Everyone, but Microsoft recommends leaving it off because unverified users could start meetings at unscheduled times. The safer arrangement is for the organizer to authenticate with the PIN or for a designated co-organizer/presenter to join through Teams and manage the lobby.^5^

References

1. Audio Conferencing common questions
2. Set the PIN length for Audio Conferencing meetings in Microsoft Teams
3. Using the lobby in Microsoft Teams meetings | Microsoft Support
4. Reset the Audio Conferencing PIN in Microsoft Teams
5. IT Admins - Manage lobby options in Microsoft Teams