SPUser user1 = web.AllUsers["i:0#.f|membership|admin@test.onmicrosoft.com"];
                        //oeGroup.AddUser(user1);
                        web.SiteGroups["Team Site Members"].AddUser(user1);
                        //oeGroup.AddUser(user1.LoginName, user1.Email, user1.Name, user1.Notes);
                        //oeGroup.Users.Add(user1.LoginName, user1.Email, user1.Name, user1.Notes);
                        oeGroup.Update();