Set the Microsoft 365 group to not be visible in the Global Address List in Exchange with C# and Microsoft Graph SDK. Ref: https://docs.microsoft.com/en-us/graph/api/group-update?view=graph-rest-1.0&tabs=http

SetHideFromAddressLists.cs

private async Task SetHideFromAddressLists(GraphServiceClient client, string groupId)
{
    var retry = true;
    var retryCount = 0;

    var body = new
    {
        hideFromAddressLists = true
    };

    while (retry)
    {
        try
        {
            var request = new HttpRequestMessage(new HttpMethod("PATCH"), client.Groups[groupId].Request().RequestUrl)
            {
                Content = new StringContent(Newtonsoft.Json.JsonConvert.SerializeObject(body), Encoding.UTF8, "application/json")
            };

            await client.AuthenticationProvider.AuthenticateRequestAsync(request);
            await client.HttpProvider.SendAsync(request);

            retry = false;
        }
        catch
        {
            await Task.Delay(5000);
            retryCount++;
        }

        if (retryCount > 10)
        {
            retry = false;
        }
    }

    return;
}