Hi @IBN
What is your conference number meaning? Do you mean the dial-in conference phone number?
If you want to change the conferencing phone number for a meeting organizer or user, you must be a Teams service admin to make these changes:
1)Log in to the Microsoft Teams admin center.
2)In the left navigation, click Users.
3)Click the user name from the list of available users.
4)Next to Audio Conferencing, click Edit.
5)Use the Toll number or Toll-free number fields to enter the numbers for the user.
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