title: Azure Active Directory Api - Add user To Group Fails
body: <p>I'm trying to add user already exists on the azure active directory to a group already exists there too , via Azure AD Graph API:</p>
  
  <pre><code>IUser userToBeAdded1 = activeDirectoryClient.Users.Where(user =&gt; user.ObjectId == "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx").ExecuteSingleAsync().Result;
  
              Group retrievedGroup = new Group();
              string searchString = "Development";
              List&lt;IGroup&gt; foundGroups = null;
              foundGroups = activeDirectoryClient.Groups.Where(group =&gt; group.DisplayName.StartsWith(searchString)).ExecuteAsync().Result.CurrentPage.ToList();
  
              if (foundGroups != null &amp;&amp; foundGroups.Count &gt; 0)
              {
                  retrievedGroup = foundGroups.First() as Group;
                  if (retrievedGroup.ObjectId != null)
                  {
                      try
                      {
                          activeDirectoryClient.Context.AddLink(retrievedGroup, "members", userToBeAdded1);
                          activeDirectoryClient.Context.SaveChanges();
                      }
                      catch (Exception ex)
                      {
                          Console.WriteLine("\nError assigning member to group. {0} {1}",
                              ex.Message, ex.InnerException != null ? ex.InnerException.Message : "");
                      }
                  }
              }
  </code></pre>
  
  <p>and each time i get the same error : 
  "The context is not currently tracking the entity."</p>
  
  <p>at this line : </p>
  
  <pre><code>activeDirectoryClient.Context.AddLink(retrievedGroup, "members", userToBeAdded1);
  </code></pre>