diff --git a/dotnet/AipsCore/Application/Common/Message/UserCanceledRequestToJoin/UserCanceledRequestToJoinMessage.cs b/dotnet/AipsCore/Application/Common/Message/UserCanceledRequestToJoin/UserCanceledRequestToJoinMessage.cs
new file mode 100644
index 0000000..7ca3eb0
--- /dev/null
+++ b/dotnet/AipsCore/Application/Common/Message/UserCanceledRequestToJoin/UserCanceledRequestToJoinMessage.cs
@@ -0,0 +1,6 @@
+using AipsCore.Application.Abstract.MessageBroking;
+using AipsCore.Application.Models.Whiteboard.Command.UserCanceledRequestToJoin;
+
+namespace AipsCore.Application.Common.Message.UserCanceledRequestToJoin;
+
+public record UserCanceledRequestToJoinMessage(UserCanceledRequestToJoinCommand Command): IMessage;
\ No newline at end of file
diff --git a/dotnet/AipsCore/Application/Common/Message/UserCanceledRequestToJoin/UserCanceledRequestToJoinMessageHandler.cs b/dotnet/AipsCore/Application/Common/Message/UserCanceledRequestToJoin/UserCanceledRequestToJoinMessageHandler.cs
new file mode 100644
index 0000000..9a35815
--- /dev/null
+++ b/dotnet/AipsCore/Application/Common/Message/UserCanceledRequestToJoin/UserCanceledRequestToJoinMessageHandler.cs
@@ -0,0 +1,19 @@
+using AipsCore.Application.Abstract;
+using AipsCore.Application.Abstract.MessageBroking;
+
+namespace AipsCore.Application.Common.Message.UserCanceledRequestToJoin;
+
+public class UserCanceledRequestToJoinMessageHandler : IMessageHandler<UserCanceledRequestToJoinMessage>
+{
+    private readonly IDispatcher _dispatcher;
+
+    public UserCanceledRequestToJoinMessageHandler(IDispatcher dispatcher)
+    {
+        _dispatcher = dispatcher;
+    }
+
+    public async Task Handle(UserCanceledRequestToJoinMessage message, CancellationToken cancellationToken)
+    {
+        await _dispatcher.Execute(message.Command, cancellationToken);
+    }
+}
\ No newline at end of file
diff --git a/dotnet/AipsCore/Application/Models/Whiteboard/Command/UserCanceledRequestToJoin/UserCanceledRequestToJoinCommand.cs b/dotnet/AipsCore/Application/Models/Whiteboard/Command/UserCanceledRequestToJoin/UserCanceledRequestToJoinCommand.cs
new file mode 100644
index 0000000..b169f89
--- /dev/null
+++ b/dotnet/AipsCore/Application/Models/Whiteboard/Command/UserCanceledRequestToJoin/UserCanceledRequestToJoinCommand.cs
@@ -0,0 +1,5 @@
+using AipsCore.Application.Abstract.Command;
+
+namespace AipsCore.Application.Models.Whiteboard.Command.UserCanceledRequestToJoin;
+
+public record UserCanceledRequestToJoinCommand(string WhiteboardId, string UserId): ICommand;
\ No newline at end of file
diff --git a/dotnet/AipsCore/Application/Models/Whiteboard/Command/UserCanceledRequestToJoin/UserCanceledRequestToJoinCommandHandler.cs b/dotnet/AipsCore/Application/Models/Whiteboard/Command/UserCanceledRequestToJoin/UserCanceledRequestToJoinCommandHandler.cs
new file mode 100644
index 0000000..b307915
--- /dev/null
+++ b/dotnet/AipsCore/Application/Models/Whiteboard/Command/UserCanceledRequestToJoin/UserCanceledRequestToJoinCommandHandler.cs
@@ -0,0 +1,40 @@
+using AipsCore.Application.Abstract.Command;
+using AipsCore.Domain.Abstract;
+using AipsCore.Domain.Common.Validation;
+using AipsCore.Domain.Models.User.ValueObjects;
+using AipsCore.Domain.Models.Whiteboard.ValueObjects;
+using AipsCore.Domain.Models.WhiteboardMembership.Enums;
+using AipsCore.Domain.Models.WhiteboardMembership.External;
+using AipsCore.Domain.Models.WhiteboardMembership.Validation;
+
+namespace AipsCore.Application.Models.Whiteboard.Command.UserCanceledRequestToJoin;
+
+public class CancelJoinRequestCommandHandler : ICommandHandler<UserCanceledRequestToJoinCommand>
+{
+    private readonly IWhiteboardMembershipRepository _whiteboardMembershipRepository;
+    private readonly IUnitOfWork _unitOfWork;
+
+    public CancelJoinRequestCommandHandler(IWhiteboardMembershipRepository whiteboardMembershipRepository, IUnitOfWork unitOfWork)
+    {
+        _whiteboardMembershipRepository = whiteboardMembershipRepository;
+        _unitOfWork = unitOfWork;
+    }
+
+    public async Task Handle(UserCanceledRequestToJoinCommand command, CancellationToken cancellationToken = default)
+    {
+        var whiteboardId = new WhiteboardId(command.WhiteboardId);
+        var userId = new UserId(command.UserId);
+        
+        var membership = await _whiteboardMembershipRepository.GetByWhiteboardAndUserAsync(whiteboardId, userId, cancellationToken);
+
+        if (membership is null)
+        {
+            throw new ValidationException(WhiteboardMembershipErrors.NotFound(whiteboardId, userId));
+        }
+        
+        membership.UpdateStatus(WhiteboardMembershipStatus.Cancelled);
+        
+        await _whiteboardMembershipRepository.SaveAsync(membership, cancellationToken);
+        await _unitOfWork.SaveChangesAsync(cancellationToken);
+    }
+}
\ No newline at end of file
diff --git a/dotnet/AipsRT/Hubs/WhiteboardHub.cs b/dotnet/AipsRT/Hubs/WhiteboardHub.cs
index 519c915..af07b91 100644
--- a/dotnet/AipsRT/Hubs/WhiteboardHub.cs
+++ b/dotnet/AipsRT/Hubs/WhiteboardHub.cs
@@ -2,6 +2,7 @@ using AipsCore.Application.Abstract;
 using AipsCore.Application.Models.Shape.Command.MoveShape;
 using AipsCore.Application.Models.Whiteboard.Command.AcceptUserRequestToJoin;
 using AipsCore.Application.Models.Whiteboard.Command.RejectUserRequestToJoin;
+using AipsCore.Application.Models.Whiteboard.Command.UserCanceledRequestToJoin;
 using AipsCore.Application.Models.Whiteboard.Query.GetMembershipStatus;
 using AipsCore.Domain.Models.WhiteboardMembership.Enums;
 using AipsRT.Model.Memberships;
@@ -21,14 +22,14 @@ public class WhiteboardHub : Hub
     private readonly WhiteboardManager _whiteboardManager;
     private readonly IMessagingService _messagingService;
     private readonly MembershipService _membershipService;
-    private readonly GetUserService _getUserService;
+    private readonly UserService _userService;
 
-    public WhiteboardHub(WhiteboardManager whiteboardManager, IMessagingService messagingService, MembershipService membershipService, GetUserService getUserService)
+    public WhiteboardHub(WhiteboardManager whiteboardManager, IMessagingService messagingService, MembershipService membershipService, UserService userService)
     {
         _whiteboardManager = whiteboardManager;
         _messagingService = messagingService;
         _membershipService = membershipService;
-        _getUserService = getUserService;
+        _userService = userService;
     }
 
     public override async Task OnDisconnectedAsync(Exception? exception)
@@ -107,7 +108,7 @@ public class WhiteboardHub : Hub
             
             if (user == null)
             {
-                user = await _getUserService.GetUser(userId);
+                user = await _userService.GetUser(userId);
             }
 
             await Clients.User(ownerId.ToString()).SendAsync("UserWaitingForApproval", user);
@@ -147,6 +148,7 @@ public class WhiteboardHub : Hub
 
         if (whiteboard != null)
         {
+            await _messagingService.CancelJoinRequest(new UserCanceledRequestToJoinCommand(whiteboard.WhiteboardId.ToString(), userId.ToString()));
             await Clients.User(whiteboard.OwnerId.ToString()).SendAsync("UserCanceledJoinRequest", userId.ToString());
         }
     }
diff --git a/dotnet/AipsRT/Model/Users/GetUserService.cs b/dotnet/AipsRT/Model/Users/UserService.cs
similarity index 77%
rename from dotnet/AipsRT/Model/Users/GetUserService.cs
rename to dotnet/AipsRT/Model/Users/UserService.cs
index 988939e..bdd7d8d 100644
--- a/dotnet/AipsRT/Model/Users/GetUserService.cs
+++ b/dotnet/AipsRT/Model/Users/UserService.cs
@@ -1,13 +1,14 @@
 using AipsCore.Application.Abstract;
 using AipsCore.Application.Models.User.Query.GetUser;
+using AipsCore.Application.Models.Whiteboard.Command.UserCanceledRequestToJoin;
 
 namespace AipsRT.Model.Users;
 
-public class GetUserService
+public class UserService
 {
     private readonly IDispatcher _dispatcher;
     
-    public GetUserService(IDispatcher dispatcher)
+    public UserService(IDispatcher dispatcher)
     {
         _dispatcher = dispatcher;
     }
diff --git a/dotnet/AipsRT/Model/Whiteboard/GetWhiteboardService.cs b/dotnet/AipsRT/Model/Whiteboard/GetWhiteboardService.cs
index 68f72ed..593ae1b 100644
--- a/dotnet/AipsRT/Model/Whiteboard/GetWhiteboardService.cs
+++ b/dotnet/AipsRT/Model/Whiteboard/GetWhiteboardService.cs
@@ -28,7 +28,8 @@ public class GetWhiteboardService
         {
             WhiteboardId = entity.Id,
             OwnerId = entity.OwnerId,
-            Owner = new User(entity.Owner.Id, entity.Owner.UserName!, entity.Owner.Email!)
+            Owner = new User(entity.Owner.Id, entity.Owner.UserName!, entity.Owner.Email!),
+            Code = entity.Code,
         };
 
         foreach (var membership in entity.Memberships)
diff --git a/dotnet/AipsRT/Model/Whiteboard/Whiteboard.cs b/dotnet/AipsRT/Model/Whiteboard/Whiteboard.cs
index 87a728e..711ff49 100644
--- a/dotnet/AipsRT/Model/Whiteboard/Whiteboard.cs
+++ b/dotnet/AipsRT/Model/Whiteboard/Whiteboard.cs
@@ -9,13 +9,14 @@ public class Whiteboard
 
     public Guid OwnerId { get; set; }
     public User Owner { get; set; } = null!;
+    
+    public string Code {get; set;}
 
     public List<User> Users { get; } = [];
 
     public List<User> ActiveUsers { get; } = [];
     public void AddActiveUser(User user) => ActiveUsers.Add(user);
-    public void RemoveActiveUser(Guid userId) 
-        => ActiveUsers.RemoveAll(u => u.UserId == userId);
+    public void RemoveActiveUser(Guid userId) => ActiveUsers.RemoveAll(u => u.UserId == userId);
     
     public List<Shape> Shapes { get; } = [];
 
@@ -48,5 +49,11 @@ public class Whiteboard
         TextShapes.Add(shape);
     }
 
-    public void AddUser(User user) => Users.Add(user);
+    public void AddUser(User user)
+    {
+        if (!Users.Contains(user))
+        {
+            Users.Add(user);
+        }
+    }
 }
\ No newline at end of file
diff --git a/dotnet/AipsRT/Program.cs b/dotnet/AipsRT/Program.cs
index 2f7711f..8949cb6 100644
--- a/dotnet/AipsRT/Program.cs
+++ b/dotnet/AipsRT/Program.cs
@@ -27,7 +27,7 @@ builder.Services.AddSingleton<IErrorMessageHandleStrategy, RtErrorHandleStrategy
 builder.Services.AddHostedService<ErrorSubscriberBackgroundService>();
 
 builder.Services.AddTransient<MembershipService>();
-builder.Services.AddTransient<GetUserService>();
+builder.Services.AddTransient<UserService>();
 
 builder.Services.AddScoped<GetWhiteboardService>();
 builder.Services.AddSingleton<WhiteboardManager>();
diff --git a/dotnet/AipsRT/Services/Interfaces/IMessagingService.cs b/dotnet/AipsRT/Services/Interfaces/IMessagingService.cs
index ca8b3cb..bbf42d7 100644
--- a/dotnet/AipsRT/Services/Interfaces/IMessagingService.cs
+++ b/dotnet/AipsRT/Services/Interfaces/IMessagingService.cs
@@ -2,6 +2,7 @@ using AipsCore.Application.Models.Shape.Command.CreateTextShape;
 using AipsCore.Application.Models.Shape.Command.MoveShape;
 using AipsCore.Application.Models.Whiteboard.Command.AcceptUserRequestToJoin;
 using AipsCore.Application.Models.Whiteboard.Command.RejectUserRequestToJoin;
+using AipsCore.Application.Models.Whiteboard.Command.UserCanceledRequestToJoin;
 using AipsRT.Model.Whiteboard.Shapes;
 
 namespace AipsRT.Services.Interfaces;
@@ -17,4 +18,5 @@ public interface IMessagingService
     
     Task AcceptedUser(AcceptUserRequestToJoinCommand command);
     Task RejectedUser(RejectUserRequestToJoinCommand command);
+    Task CancelJoinRequest(UserCanceledRequestToJoinCommand command);
 }
\ No newline at end of file
diff --git a/dotnet/AipsRT/Services/MessagingService.cs b/dotnet/AipsRT/Services/MessagingService.cs
index 7789852..ecd08c0 100644
--- a/dotnet/AipsRT/Services/MessagingService.cs
+++ b/dotnet/AipsRT/Services/MessagingService.cs
@@ -6,6 +6,7 @@ using AipsCore.Application.Common.Message.AddRectangle;
 using AipsCore.Application.Common.Message.AddTextShape;
 using AipsCore.Application.Common.Message.MoveShape;
 using AipsCore.Application.Common.Message.RejectUserRequestToJoin;
+using AipsCore.Application.Common.Message.UserCanceledRequestToJoin;
 using AipsCore.Application.Models.Shape.Command.CreateArrow;
 using AipsCore.Application.Models.Shape.Command.CreateLine;
 using AipsCore.Application.Models.Shape.Command.CreateRectangle;
@@ -13,6 +14,7 @@ using AipsCore.Application.Models.Shape.Command.CreateTextShape;
 using AipsCore.Application.Models.Shape.Command.MoveShape;
 using AipsCore.Application.Models.Whiteboard.Command.AcceptUserRequestToJoin;
 using AipsCore.Application.Models.Whiteboard.Command.RejectUserRequestToJoin;
+using AipsCore.Application.Models.Whiteboard.Command.UserCanceledRequestToJoin;
 using AipsRT.Model.Whiteboard.Shapes;
 using AipsRT.Services.Interfaces;
 
@@ -116,4 +118,10 @@ public class MessagingService : IMessagingService
         var message = new RejectUserRequestToJoinMessage(command);
         await _messagePublisher.PublishAsync(message);   
     }
+
+    public async Task CancelJoinRequest(UserCanceledRequestToJoinCommand command)
+    {
+        var message = new UserCanceledRequestToJoinMessage(command);
+        await _messagePublisher.PublishAsync(message);  
+    }
 }
\ No newline at end of file
diff --git a/dotnet/AipsRT/Services/RtErrorHandleStrategy.cs b/dotnet/AipsRT/Services/RtErrorHandleStrategy.cs
index 3f14796..2669f2f 100644
--- a/dotnet/AipsRT/Services/RtErrorHandleStrategy.cs
+++ b/dotnet/AipsRT/Services/RtErrorHandleStrategy.cs
@@ -18,9 +18,16 @@ public class RtErrorHandleStrategy : IErrorMessageHandleStrategy
     
     public async Task Handle(ErrorMessage message, CancellationToken cancellationToken)
     {
+        var activeUsers = _whiteboardManager.GetWhiteboard(message.WhiteboardId)!.ActiveUsers;
+        
         await _whiteboardManager.LoadWhiteboard(message.WhiteboardId);
         
         var whiteboard = _whiteboardManager.GetWhiteboard(message.WhiteboardId)!;
+
+        foreach (var user in activeUsers)
+        {
+            whiteboard.AddActiveUser(user);
+        }
         
         await _hubContext.Clients
             .Group(whiteboard.WhiteboardId.ToString())
diff --git a/dotnet/AipsWorker/Messages/MessageTypesProvider.cs b/dotnet/AipsWorker/Messages/MessageTypesProvider.cs
index a2c62b4..d8089e4 100644
--- a/dotnet/AipsWorker/Messages/MessageTypesProvider.cs
+++ b/dotnet/AipsWorker/Messages/MessageTypesProvider.cs
@@ -6,6 +6,7 @@ using AipsCore.Application.Common.Message.AddRectangle;
 using AipsCore.Application.Common.Message.AddTextShape;
 using AipsCore.Application.Common.Message.MoveShape;
 using AipsCore.Application.Common.Message.RejectUserRequestToJoin;
+using AipsCore.Application.Common.Message.UserCanceledRequestToJoin;
 
 namespace AipsWorker.Messages;
 
@@ -21,7 +22,8 @@ public class MessageTypesProvider : IMessageTypesProvider
             typeof(AddTextShapeMessage),
             typeof(MoveShapeMessage),
             typeof(AcceptUserRequestToJoinMessage),
-            typeof(RejectUserRequestToJoinMessage)
+            typeof(RejectUserRequestToJoinMessage),
+            typeof(UserCanceledRequestToJoinMessage)
         ];
     }
 }
\ No newline at end of file
diff --git a/front/src/components/whiteboard/WhiteboardToolbar.vue b/front/src/components/whiteboard/WhiteboardToolbar.vue
index 23739ed..492c9ac 100644
--- a/front/src/components/whiteboard/WhiteboardToolbar.vue
+++ b/front/src/components/whiteboard/WhiteboardToolbar.vue
@@ -23,6 +23,12 @@ const colors = ['#4f9dff', '#ff4f4f', '#4fff4f', '#ffff4f', '#ff4fff', '#ffffff'
 
 const isReadOnly = computed(() => sessionStore.selectedTool === 'hand' && !!sessionStore.selectedShape)
 
+const isOwner = computed(() => {
+  const wb = sessionStore.whiteboard
+  if (!wb || !auth.user) return false
+  return wb.ownerId === auth.user.userId
+})
+
 const showProperties = computed(() => {
   if (['rectangle', 'arrow', 'line', 'text'].includes(sessionStore.selectedTool)) return true
   if (sessionStore.selectedTool === 'hand' && sessionStore.selectedShape) return true
@@ -61,7 +67,7 @@ const displayTextSize = computed(() => {
 
 const showCopiedTooltip = ref(false)
 
-const whiteboardCode = computed(() => infoStore.getCurrentWhiteboard()?.code || '')
+const whiteboardCode = computed(() => sessionStore.whiteboard!.code)
 
 const copyCodeToClipboard = async () => {
   console.info(whiteboardCode.value)
@@ -166,7 +172,7 @@ const copyCodeToClipboard = async () => {
         </div>
       </div>
 
-      <div class="position-relative mb-2">
+      <div v-if="isOwner" class="position-relative mb-2">
         <button
           class="btn btn-sm btn-outline-primary w-100"
           @click="copyCodeToClipboard"
diff --git a/front/src/services/signalr.ts b/front/src/services/signalr.ts
index 0477c6b..c6b3dad 100644
--- a/front/src/services/signalr.ts
+++ b/front/src/services/signalr.ts
@@ -22,8 +22,23 @@ export class SignalRService {
   }
 
   async start(): Promise<void> {
-    if (this.connection.state === HubConnectionState.Disconnected) {
+    if (this.connection.state !== HubConnectionState.Disconnected) return;
+
+    try {
       await this.connection.start();
+    } catch (err: any) {
+      if (err.statusCode === 401 || err.message?.includes("401")) {
+        const authStore = useAuthStore();
+        try {
+          await authStore.tryRefresh();
+
+          await this.connection.start();
+        } catch (refreshErr) {
+          throw refreshErr;
+        }
+      } else {
+        throw err;
+      }
     }
   }
 
diff --git a/front/src/stores/auth.ts b/front/src/stores/auth.ts
index 52042f4..e49ece3 100644
--- a/front/src/stores/auth.ts
+++ b/front/src/stores/auth.ts
@@ -151,6 +151,7 @@ export const useAuthStore = defineStore('auth', () => {
     isAuthenticated,
     isLoading,
     error,
+    tryRefresh,
     initialize,
     login,
     signup,
diff --git a/front/src/stores/whiteboard.ts b/front/src/stores/whiteboard.ts
index c3eb8a4..81687db 100644
--- a/front/src/stores/whiteboard.ts
+++ b/front/src/stores/whiteboard.ts
@@ -113,6 +113,7 @@ export const useWhiteboardStore = defineStore('whiteboard', () => {
     whiteboardHubService.onAccepted(() => {
       const infoStore = useWhiteboardsStore()
       infoStore.stopWaitingToJoin()
+      isLoading.value = false
     })
 
     whiteboardHubService.onRejected(() => {
diff --git a/front/src/types/whiteboard.ts b/front/src/types/whiteboard.ts
index 49113ef..acac692 100644
--- a/front/src/types/whiteboard.ts
+++ b/front/src/types/whiteboard.ts
@@ -33,6 +33,7 @@ export interface TextShape extends Shape {
 export interface Whiteboard {
   whiteboardId: string
   ownerId: string
+  code: string
   rectangles: Rectangle[]
   arrows: Arrow[]
   lines: Line[]