To add/remove users from Matter, simply add or remove them from the Microsoft Teams team/channel.

Our Web App syncs with Microsoft Teams every 24 hours. During this sync, we add/remove channel members to the Web App workspace.

If you add someone to the channel and you don't see them in the Web App, you'll need to wait 24 hours for the API sync.

Note: You may need to be a Microsoft Teams Team Owner/Admin to add or remove users.