How to update an existing object

Hey, I have table Relationship. It has columns Person ( 1-1 to Person Table) and Friends(1-N to Person table). I got in Android list of all friends i.e.

List<Person> friends 

I added one more person to that list:


and updated Relationship class:

and now I want to update it on sarver:

relationship.saveAsync(new AsyncCallback<Relationship>() {
 public void handleResponse(Relationship savedContact) {
 Log.v("It works", "It works");

 public void handleFault(BackendlessFault backendlessFault) {
 Log.v("Nooo,it doesn't work", backendlessFault.toString());

I got this exception: BackendlessFault{ code: ‘36’, message: ‘Duplicate entry for column ‘user’’ }

Any updates on this? I’m getting the same issue? …The docs don’t help in this case.

Hi Mladen,
Could you please show, how do you get the list of friends ?