diff --git a/RobotApp.Client/Pages/Logs.razor b/RobotApp.Client/Pages/Logs.razor
index b4c5bef..fde3dc9 100644
--- a/RobotApp.Client/Pages/Logs.razor
+++ b/RobotApp.Client/Pages/Logs.razor
@@ -77,6 +77,13 @@
     </div>
 </div>
 
+<script>
+    window.ScrollToBottom = (element) => {
+    if (element) {
+        element.scrollTop = element.scrollHeight;
+    }
+};
+</script>
 
 @code {
     private DateTime DateLog = DateTime.Today;
diff --git a/RobotApp.Client/Pages/Logs.razor.css b/RobotApp.Client/Pages/Logs.razor.css
index 2a3ae7a..96663ec 100644
--- a/RobotApp.Client/Pages/Logs.razor.css
+++ b/RobotApp.Client/Pages/Logs.razor.css
@@ -23,7 +23,7 @@
 
 .log-level {
     display: inline-block;
-    width: 46px;
+    width: 60px;
 }
 
 .log-head {
diff --git a/RobotApp.Client/Pages/RobotConfigManager.razor.cs b/RobotApp.Client/Pages/RobotConfigManager.razor.cs
index 45637ba..c71f006 100644
--- a/RobotApp.Client/Pages/RobotConfigManager.razor.cs
+++ b/RobotApp.Client/Pages/RobotConfigManager.razor.cs
@@ -560,10 +560,14 @@ public partial class RobotConfigManager
 
     private async Task LoadConfig()
     {
+        IsLoading = true;
+        StateHasChanged();
         var response = await (await Http.PostAsync($"api/RobotConfigs/load", null)).Content.ReadFromJsonAsync<MessageResult>();
         if (response is null) Snackbar.Add("Failed to load config", Severity.Warning);
         else if (!response.IsSuccess) Snackbar.Add(response.Message ?? "Failed to load config", Severity.Warning);
         else Snackbar.Add("Config loaded", Severity.Success);
+
+        IsLoading = false;
         StateHasChanged();
     }
 }
diff --git a/RobotApp/Services/MQTTClient.cs b/RobotApp/Services/MQTTClient.cs
index a1e6d48..95c697c 100644
--- a/RobotApp/Services/MQTTClient.cs
+++ b/RobotApp/Services/MQTTClient.cs
@@ -147,11 +147,11 @@ public class MQTTClient : IAsyncDisposable
 
             MqttClient = MqttClientFactory.CreateMqttClient();
 
-            //MqttClient.ApplicationMessageReceivedAsync -= OnMessageReceived;
+            MqttClient.ApplicationMessageReceivedAsync -= OnMessageReceived;
             MqttClient.ApplicationMessageReceivedAsync += OnMessageReceived;
-            //MqttClient.DisconnectedAsync -= OnDisconnected;
+            MqttClient.DisconnectedAsync -= OnDisconnected;
             MqttClient.DisconnectedAsync += OnDisconnected;
-            while (!cancellationToken.IsCancellationRequested)
+            while (!cancellationToken.IsCancellationRequested && !IsDisposed)
             {
                 try
                 {
@@ -168,7 +168,11 @@ public class MQTTClient : IAsyncDisposable
                 {
                     Logger.Error($"Lỗi khi tạo MQTT client: {ex.Message}");
                 }
-                await Task.Delay(3000, cancellationToken);
+                try
+                {
+                    await Task.Delay(3000, cancellationToken);
+                }
+                catch { }
             }
         }
         else throw new ObjectDisposedException(nameof(MQTTClient));
@@ -219,10 +223,10 @@ public class MQTTClient : IAsyncDisposable
             var tlsOptions = new MqttClientTlsOptionsBuilder()
                             .UseTls(true)
                             .WithSslProtocols(System.Security.Authentication.SslProtocols.Tls12 | System.Security.Authentication.SslProtocols.Tls13)
-                            //.WithCertificateValidationHandler(ValidateCertificates)
+                            .WithCertificateValidationHandler(ValidateCertificates)
                             .WithClientCertificatesProvider(new MQTTClientCertificatesProvider(VDA5050Setting.CerFile, VDA5050Setting.KeyFile))
                             .Build();
-            builder =  builder.WithTlsOptions(tlsOptions);
+            builder = builder.WithTlsOptions(tlsOptions);
         }
         MqttClientOptions = builder.Build();
     }
@@ -251,42 +255,42 @@ public class MQTTClient : IAsyncDisposable
     {
         //if (!IsDisposed)
         //{
-            if (MqttClient is null) throw new Exception("Kết nối tới broker chưa được khởi tạo nhưng đã yêu cầu subscribe");
-            if (!MqttClient.IsConnected) throw new Exception("Kết nối tới broker chưa thành công nhưng đã yêu cầu subscribe");
+        if (MqttClient is null) throw new Exception("Kết nối tới broker chưa được khởi tạo nhưng đã yêu cầu subscribe");
+        if (!MqttClient.IsConnected) throw new Exception("Kết nối tới broker chưa thành công nhưng đã yêu cầu subscribe");
 
 
-            while (!cancellationToken.IsCancellationRequested)
+        while (!cancellationToken.IsCancellationRequested)
+        {
+            try
             {
-                try
+                var response = await MqttClient.SubscribeAsync(MqttClientSubscribeOptions, cancellationToken);
+                bool isSuccess = true;
+                foreach (var item in response.Items)
                 {
-                    var response = await MqttClient.SubscribeAsync(MqttClientSubscribeOptions, cancellationToken);
-                    bool isSuccess = true;
-                    foreach (var item in response.Items)
+                    if (item.ResultCode == MqttClientSubscribeResultCode.GrantedQoS0 ||
+                        item.ResultCode == MqttClientSubscribeResultCode.GrantedQoS1 ||
+                        item.ResultCode == MqttClientSubscribeResultCode.GrantedQoS2)
                     {
-                        if (item.ResultCode == MqttClientSubscribeResultCode.GrantedQoS0 ||
-                            item.ResultCode == MqttClientSubscribeResultCode.GrantedQoS1 ||
-                            item.ResultCode == MqttClientSubscribeResultCode.GrantedQoS2)
-                        {
-                            Logger.Info($"Subscribe thành công cho topic: {item.TopicFilter.Topic} với QoS: {item.ResultCode}");
-                        }
-                        else
-                        {
-                            Logger.Warning($"Subscribe thất bại cho topic: {item.TopicFilter.Topic}. Lý do: {response.ReasonString}");
-                            isSuccess = false;
-                            break;
-                        }
+                        Logger.Info($"Subscribe thành công cho topic: {item.TopicFilter.Topic} với QoS: {item.ResultCode}");
+                    }
+                    else
+                    {
+                        Logger.Warning($"Subscribe thất bại cho topic: {item.TopicFilter.Topic}. Lý do: {response.ReasonString}");
+                        isSuccess = false;
+                        break;
                     }
-                    if (isSuccess) break;
-                }
-                catch (Exception ex)
-                {
-                    Logger.Error($"Lỗi khi subscribe: {ex.Message}");
-                }
-                if (!cancellationToken.IsCancellationRequested && !IsDisposed)
-                {
-                    await Task.Delay(3000, cancellationToken);
                 }
+                if (isSuccess) break;
             }
+            catch (Exception ex)
+            {
+                Logger.Error($"Lỗi khi subscribe: {ex.Message}");
+            }
+            if (!cancellationToken.IsCancellationRequested && !IsDisposed)
+            {
+                await Task.Delay(3000, cancellationToken);
+            }
+        }
         //}
         //else throw new ObjectDisposedException(nameof(MQTTClient));
     }
diff --git a/RobotApp/Services/Robot/RobotConfiguration.cs b/RobotApp/Services/Robot/RobotConfiguration.cs
index e2fe8c4..e1886e8 100644
--- a/RobotApp/Services/Robot/RobotConfiguration.cs
+++ b/RobotApp/Services/Robot/RobotConfiguration.cs
@@ -57,8 +57,8 @@ public class RobotConfiguration(IServiceProvider ServiceProvider, Logger<RobotCo
                 if (IsReady)
                 {
                     var robotConnection = scope.ServiceProvider.GetRequiredService<RobotConnection>();
-                    await robotConnection.StopConnection();
                     robotConnection.StartConnection();
+                    await Task.Delay(1000);
                 }
             }
             else throw new Exception("Chưa có cấu hình VDA5050.");
diff --git a/RobotApp/Services/Robot/RobotConnection.cs b/RobotApp/Services/Robot/RobotConnection.cs
index e3b8dd8..c3f6abd 100644
--- a/RobotApp/Services/Robot/RobotConnection.cs
+++ b/RobotApp/Services/Robot/RobotConnection.cs
@@ -3,19 +3,21 @@ using RobotApp.VDA5050;
 using RobotApp.VDA5050.InstantAction;
 using RobotApp.VDA5050.Order;
 using System.Text.Json;
+using System.Threading;
 
 namespace RobotApp.Services.Robot;
 
-public class RobotConnection(RobotConfiguration RobotConfiguration, 
+public class RobotConnection(RobotConfiguration RobotConfiguration,
                              Logger<RobotConnection> Logger,
                              Logger<MQTTClient> MQTTClientLogger)
 {
-    private readonly VDA5050Setting VDA5050Setting = RobotConfiguration.VDA5050Setting;
     private MQTTClient? MqttClient;
 
     public bool IsConnected => MqttClient is not null && MqttClient.IsConnected;
     public event Action<OrderMsg>? OrderUpdated;
     public event Action<InstantActionsMsg>? ActionUpdated;
+    private readonly SemaphoreSlim _connectionSemaphore = new(1, 1);
+    private CancellationTokenSource? _connectionCancel;
 
 
     private void OrderChanged(string data)
@@ -50,7 +52,7 @@ public class RobotConnection(RobotConfiguration RobotConfiguration,
 
     public async Task<MessageResult> Publish(string topic, string data)
     {
-        if (MqttClient is not null && MqttClient.IsConnected) return await MqttClient.PublishAsync($"{VDA5050Setting.TopicPrefix}/{VDA5050Setting.Manufacturer}/{RobotConfiguration.SerialNumber}/{topic}", data);
+        if (MqttClient is not null && MqttClient.IsConnected) return await MqttClient.PublishAsync($"{RobotConfiguration.VDA5050Setting.TopicPrefix}/{RobotConfiguration.VDA5050Setting.Manufacturer}/{RobotConfiguration.SerialNumber}/{topic}", data);
         return new(false, "Chưa có kết nối tới broker");
     }
     public void StartConnection()
@@ -58,16 +60,29 @@ public class RobotConnection(RobotConfiguration RobotConfiguration,
         Task.Run(async () =>
         {
             await StartConnectionAsync(CancellationToken.None);
-            Logger.Info("Robot đã kết nối tới Fleet Manager.");
+            if(IsConnected)Logger.Info("Robot đã kết nối tới Fleet Manager.");
         });
     }
     public async Task StartConnectionAsync(CancellationToken cancellationToken)
     {
-        MqttClient = new MQTTClient(RobotConfiguration.SerialNumber, VDA5050Setting, MQTTClientLogger);
-        MqttClient.OrderChanged += OrderChanged;
-        MqttClient.InstanceActionsChanged += InstanceActionsChanged;
-        await MqttClient.ConnectAsync(cancellationToken);
-        await MqttClient.SubscribeAsync(cancellationToken);
+        try
+        {
+            await StopConnection();
+            _connectionCancel?.Cancel();
+            if (_connectionSemaphore.Wait(1000, cancellationToken))
+            {
+                _connectionCancel = CancellationTokenSource.CreateLinkedTokenSource(cancellationToken);
+                MqttClient = new MQTTClient(RobotConfiguration.SerialNumber, RobotConfiguration.VDA5050Setting, MQTTClientLogger);
+                MqttClient.OrderChanged += OrderChanged;
+                MqttClient.InstanceActionsChanged += InstanceActionsChanged;
+                await MqttClient.ConnectAsync(_connectionCancel.Token);
+                if(MqttClient is not null) await MqttClient.SubscribeAsync(_connectionCancel.Token);
+            }
+        }
+        finally
+        {
+            _connectionSemaphore.Release();
+        }
     }
 
     public async Task StopConnection()