Hi AgnosticAnalytics-6769,
It needs to set up Audio Conferencing for Teams to enable the dial in meeting feature as the following steps:
- Step 1: Find out if Audio Conferencing is available in your country/region
- Step 2: Get and assign licenses
- Step 3: Get service numbers for your conferencing bridges
- Step 4: Assign a service number to the conferencing bridge
- Step 5: Set the default and alternate languages for a conferencing bridge
- Step 6: Set your conferencing bridge settings
- Step 7: Assign dial-in phone numbers for users who lead meetings
- Step 8: Set up meeting invitations (optional)
For more details, please refer to this article: https://learn.microsoft.com/en-us/microsoftteams/set-up-audio-conferencing-in-teams#step-7-assign-dial-in-phone-numbers-for-users-who-lead-meetings.