Moving a group of cubes from two players

Hi, I try to implement a little block building challenge.

3 Cubes are placed on each other.
They instantiated using photonnetwork and each has a photonview.
I instantiate from the master player.
Each time i grab a cube, I want that the whole group gets the ownership of the grabbing player.
The idea is that all movements are synchronized either form player one or player two.
It works in one direction and i also see the change of the ownership.
But at the moment the second player starts moving... I assume he has the ownership... the cube vanishes in the scene of the first player.

Each cube has this script (the grabbing is done by changing the parent.... so I chose the OnBefore...)

Thanks for Help, Marc

using Photon.Pun;
using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class changeOwnerRIS : MonoBehaviourPun
GameObject[] allMoveables;
private void Start()
allMoveables = GameObject.FindGameObjectsWithTag("Moveable");

private void OnBeforeTransformParentChanged()
//PhotonView photonView1 = PhotonView.Get(this);
foreach (GameObject Moveable in allMoveables)
PhotonView photonView1 = PhotonView.Get(Moveable);
if (photonView1 != null)
Debug.Log("photonView.Owner: " + photonView.Owner);