Manage Microsoft Teams chat membership

From the submitter: Microsoft Teams does not automatically add new members of a distribution list to an existing Teams chat. When you initiate a chat using a distribution list, Teams expands the list at that moment to include the current members. This means that any subsequent changes to the distribution list—such as adding or removing members—will not reflect in the existing chat. If you want to include new members who were added to the distribution list after the chat was created, you'll need to manually add them to the chat.

Community author

Nathan Collings at Holland & Barrett