How do I unassign a DID that was assigned as a conference bridge number and reassign as an autoattendant?

Hi @Jim Catrett

Unassign the service phone number for the conference bridge

When you unassign a phone number from a conferencing bridge, users can't join any meetings using that phone number anymore. Because the phone number is changing, you should update all users with a changing phone number as their default. Update their meeting invites before the phone number is unassigned from the conferencing bridge.

Please start Windows PowerShell and follow the steps below:

Step 1 - Update users who have the phone number to be unassigned as one of their default numbers

Replace the default toll or toll-free number for all users who have the number to be unassigned as a default number and start the process of rescheduling their meetings. To the toll or toll-free number, run the following command:

Set-CsOnlineDialInConferencingUserDefaultNumber -FromNumber <Number to be removed> -ToNumber <Number to be set as new default> -NumberType <"Toll" or "Toll-Free"> -RescheduleMeetings

Step 2 - View meeting migration status using Windows PowerShell

All meetings are rescheduled once there are no operations in Pending or In-Progress state.

Get-CsMeetingMigrationStatus -SummaryOnly

Step 3 - Unassign the old phone number from the audio conferencing bridge

Use the Unregister-CsOnlineDialInConferencingServiceNumber cmdlet to unregister a Toll or Toll free number from a conference bridge.

Unregister-CsOnlineDialInConferencingServiceNumber -identity "toll number to be removed" -bridgeId "Conference Bridge ID"
Unregister-CsOnlineDialInConferencingServiceNumber -identity "toll free number to be removed" -bridgeId "Conference Bridge ID"

Note: To find the Conference Bridge ID, run the following PowerShell: Get-CsOnlineDialInConferencingBridge.

Assign a service phone number to the conference bridge

Please log in to the Microsoft Teams admin center and follow these steps:

1. On the left navigation pane, go to Voice > Phone numbers.
2. Select the phone number from the list, and select Edit.
3. On the Edit page, under Assigned to, expand the dropdown and then select Conference bridge > Apply.

If you encounter the problem that the Unassign button isn't available, or you need more detailed information please refer to this documentation.

Thanks for your understanding and support.

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