Nested fragment data always the same in Relay

Question

I'm new to Relay and am having an issue with nested data on a fragment.

The following query returns the correct data when I test in it graphiql so I am confident my schema is correct.

 {
  viewer {
    customers {
      name
      billing_address {
        city
      }
    } 
  }
}

However, when I use the above query with Relay the customer.name will be correct but customer.billing_address.city is the same for every customer. It's confusing to me why some of the data would be correct while the nested data would just be copied.

I would appreciate any help with the issue and if anymore information is needed I would be glad to add it. Below is the only Relay code currently in my project and where I believe the issue may be.

class App extends Component {
  render() {
    console.log(this.props.viewer.customers);
    return (
      <div>
      {this.props.viewer.customers.map((customer) => (
        <div>
          <div>{customer.name}</div>
          <div>{customer.billing_address.city}</div>
        </div>
      ))}
      </div>
    );
  }
}

class AppHomeRoute extends Relay.Route {
  static queries = {
    viewer: () => Relay.QL`
      query {
        viewer
      }
    `,
  };
  static routeName = 'AppHomeRoute';
}

const AppContainer =  Relay.createContainer(App, {
  fragments: {
    viewer: () => Relay.QL`
      fragment on Viewer {
        customers{
          name
          billing_address{
            city
          }
        }
      }`
  },
});

ReactDOM.render(
  <Relay.RootContainer
    Component={AppContainer}
    route={new AppHomeRoute()}
  />,
  document.getElementById('root')
);

Answer 1

One possible problem could by how you resolve billing_address in your GraphQL schema. Did you include an field :id, !types.ID or globalIdField in your billing_address GraphQL type? Posting your GraphQL schema may also help.