Hi @IBN ,
We are having an automatic group member assignment to a group which isn't a dynamic group. The service applying the add operation says Microsoft Teams services.
Are you referring to the org-wide team which automatically pulls in every user in the organization? See Create an organization-wide team in Microsoft Teams.
If this is the case, you can log in Teams as global admin, go to the team name, click More options > Edit team, change the team type to "Private" or "Public" instead of "org-wide", then you would be able to manually adjust the team membership.
If this is not the case, you can share more details or a screenshot without privacy information so that we can understand better about your issue.
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