How to change a Material for different clients whit MLAPI?!

Good day,
i try to make a new multiplayergame with MLAPI i started this day so i ont have much experiecense btw. I passed all what i need but yet i dont pass the goal, i have a playerspawner-Script they are colored with one btw. the same Material(I spawn the Prefab). But rigth now i want to make a Color choser the Problem is when i change my Material all characters change i first tryed the Color chooser whith a video, in the Video the Person chnaged it with the renderer of the object / prefab (ColourRenderer.material.SetColor("_BaseColor", Colours[newColorIndex]) after i searched on the Web and in the Documentations usw. but i found nothing to this theme and so i am here. (I have images where i give the numbers this work perfectly i tested it whith a print method, and than i have a array of colors that i put in the PlayerColor script bzw. when i get index 1 color Array one is the Actual Color)
Thanks to advance to all!
*Details*
Unity version: 2021.1.17f1,
MLAPI version: 0.1.0
(The Color change code is down bellow)

Code (CSharp):

1. //ColourPicker (Is in a emty object where all canvasess are in!)
2. using MLAPI;
3. using MLAPI.Connection;
4. using UnityEngine;
5. namespace FyMa2618.UMT.NetworkVariables
6. {
7.     public class ColourPicker : MonoBehaviour
8.     {
9.         public void SelectColor(int colorIndex)
10.         {
11.             print(colorIndex);
12.             ulong localClientId = NetworkManager.Singleton.LocalClientId;
13.             if(!NetworkManager.Singleton.ConnectedClients.TryGetValue(localClientId, out NetworkClient networkClient))
14.             {
15.                 return;
16.             }
17.             if(!networkClient.PlayerObject.TryGetComponent<PlayerColor>(out PlayerColor playerColor))
18.             {
19.                 return;
20.             }
21.             playerColor.SetColorServerRpc((byte)colorIndex);
22.         }
23.     }
24. }
25. //PlayerColor(Is on the Player prefab)
26. using MLAPI;
27. using MLAPI.Messaging;
28. using MLAPI.NetworkVariable;
29. using UnityEngine;
30. namespace FyMa2618.UMT.NetworkVariables
31. {
32.     public class PlayerColor : NetworkBehaviour
33.     {
34.         public Renderer ColourRenderer;
35.         public Material player;
36.         public Color[] Colours;
37.         private NetworkVariableByte colorIndex = new NetworkVariableByte();
38.         [ServerRpc]
39.         public void SetColorServerRpc(byte newColorIndex)
40.         {
41.             if(newColorIndex > 3) { return; }
42.             colorIndex.Value = newColorIndex;
43.         }
44.         private void OnEnable()
45.         {
46.             print("Enable");
47.             colorIndex.OnValueChanged += OnColorChanged;
48.         }
49.         private void OnDisable()
50.         {
51.             print("Disbale");
52.             colorIndex.OnValueChanged -= OnColorChanged;
53.         }
54.         private void OnColorChanged(byte oldColorIndex, byte newColorIndex)
55.         {
56.             if(!IsClient) { return; }
57.             print("Suces");
58.             //ColourRenderer.material.SetColor("_BaseColor", Colours[newColorIndex]);
59.             player.color = Colours[newColorIndex];
60.             print("AASuces");
61.         }
62.     }
63. }
64.  

Sory that there is a emojy its because i maked ) ;

 

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