Simple chat sync problem

Hi guys,
I've today to make a little networked chat
I try to know what's the problem, couldn't know, I'm using the Unity 5 UI and UNET
here's the code

Code (CSharp):

1. using UnityEngine;
2. using System.Collections;
3. using UnityEngine.UI;
4. using UnityEngine.Networking;
5.  
6. public class PlayerChat : NetworkBehaviour {
7.  
8.     [SerializeField]
9.     private Text chatText;
10.     [SerializeField]
11.     private InputField chatInput;
12.     [SerializeField]
13.     private Button chatButton;
14.  
15.     void OnEnable()
16.     {
17.         chatButton.onClick.AddListener(delegate { SendTextChat(); });
18.         chatInput.onEndEdit.AddListener(delegate { SendTextChat(); });
19.     }
20.  
21.     void SendTextChat()
22.     {
23.         Debug.Log(chatInput.text);
24.         if(chatInput.text != string.Empty)
25.         {
26.            string textToSend = transform.name + " : " + chatInput.text;
27.            CmdSendText(textToSend);
28.         }
29.        
30.     }
31.  
32.  
33.     [Command]
34.     void CmdSendText(string text)
35.     {
36.         RpcSendText(text);
37.     }
38.  
39.     [ClientRpc]
40.     void RpcSendText(string text)
41.     {
42.         chatText.text += text;
43.         chatText.text += "\n";
44.         chatInput.text = "";
45.     }
46. }
47.  

If you want a screenshot of the hierarchy, just tell and i'll attach it
Help me plz

 

I tried to use Debug.Log on text for the ClientRpc void, it works well
Sometimes i think i should make the chat with the debug log xDD
Help plz