diff --git a/Presentation/HushianWebApp/Components/AttachedtoComponent.razor b/Presentation/HushianWebApp/Components/AttachedtoComponent.razor
new file mode 100644
index 0000000..d5eab1c
--- /dev/null
+++ b/Presentation/HushianWebApp/Components/AttachedtoComponent.razor
@@ -0,0 +1,50 @@
+@using Common.Dtos.Exper
+@using HushianWebApp.Service
+@inject GroupService groupService;
+@inject UserService userService;
+@inject HushianWebApp.Services.ILocalStorageService localStorageService;
+@inject ChatService chatService;
+@inject ToastService toastService
+@if (!Spinnervisible)
+{
+    <div class="row">
+        <div class="col-md-12 col-sm-12" style="margin-bottom:15px">
+            <AutoComplete @bind-Value="ExperName"
+            TItem="Read_ExperDto"
+            DataProvider="DataProvider"
+            PropertyName="FullName"
+            Placeholder="جستجو در کاربران..."
+            OnChanged="(Read_ExperDto exper) => OnAutoCompleteChanged(exper)"/>
+        </div>
+    </div>
+}
+@code {
+    private string? ExperName;
+    private bool Spinnervisible = false;
+    [Parameter]  public int chatID { get; set; }
+    [Parameter] public EventCallback OnMultipleOfThree { get; set; }
+    public List<Read_ExperDto> CoExpers { get; set; }
+    = new();
+    protected override async Task OnParametersSetAsync()
+    {
+        await base.OnParametersSetAsync();
+    }
+}
+    @functions {
+    private async Task<AutoCompleteDataProviderResult<Read_ExperDto>> DataProvider(AutoCompleteDataProviderRequest<Read_ExperDto> request)
+    {
+        CoExpers = await userService.GetExpersCompany();
+        return await Task.FromResult(new AutoCompleteDataProviderResult<Read_ExperDto> { Data = CoExpers.Where(w => w.FullName.Contains(request.Filter.Value)), TotalCount = CoExpers.Count() });
+    }
+
+    private async Task OnAutoCompleteChanged(Read_ExperDto exper)
+    {
+        Spinnervisible = true;
+        if(await chatService.Attachedto(exper.ID, chatID))
+        {
+           await OnMultipleOfThree.InvokeAsync();
+        }
+        else toastService.Notify(new ToastMessage(ToastType.Danger, "خطا در پیوست"));
+        Spinnervisible = false;
+    }
+   }
diff --git a/Presentation/HushianWebApp/Pages/Chat.razor b/Presentation/HushianWebApp/Pages/Chat.razor
index 5d33694..7feca37 100644
--- a/Presentation/HushianWebApp/Pages/Chat.razor
+++ b/Presentation/HushianWebApp/Pages/Chat.razor
@@ -3,6 +3,7 @@
 @using Common.Dtos.Conversation
 @using Common.Dtos.Group
 @using Common.Enums
+@using HushianWebApp.Components
 @using HushianWebApp.Service
 @inject ChatService chatService
 @inject GroupService groupService
@@ -10,6 +11,7 @@
 @inject IJSRuntime JS
 @inject ToastService toastService
 <ConfirmDialog @ref="dialog" />
+<Modal @ref="modal" IsVerticallyCentered="true" IsScrollable="true" />
 <PageTitle>گفتمان</PageTitle>
 <div class="container-fluid">
     <div class="row" style="height:85vh">
@@ -158,8 +160,9 @@
                                 <Icon Name="IconName.Escape" /> اتمام گفتگو
                             </Button>
 
-                            <Button Color="ButtonColor.Secondary" Size=ButtonSize.ExtraSmall Outline="true" Class="toexper-btn">
-                                <Icon Name="IconName.EnvelopeArrowUp" /> پیوست به...
+                            <Button Color="ButtonColor.Secondary" Size=ButtonSize.ExtraSmall Outline="true" Class="toexper-btn" @onclick="onclickAttachedto">
+                                <Icon Name="IconName.EnvelopeArrowUp"
+                               /> پیوست به...
                             </Button>
                         }
                         else if (ChatCurrent.status == Common.Enums.ConversationStatus.Finished
@@ -283,7 +286,7 @@
     string SelectedChatUserName = "مهدی ربیع نژاد";
     private bool _shouldObserveVisibility = false;
     private ConfirmDialog dialog = default!;
-
+    private Modal modal = default!;
 }
 @functions {
     protected override async Task OnInitializedAsync()
@@ -369,6 +372,20 @@
         // StateHasChanged();
         await Task.CompletedTask;
     }
+    async Task onclickAttachedto()
+    {
+        Dictionary<string, object> parameters = new Dictionary<string, object>();
+        parameters.Add("chatID",ChatCurrent.ID);
+        parameters.Add("OnMultipleOfThree", EventCallback.Factory.Create(this, CallBackAttachedto));
+
+        await modal.ShowAsync<AttachedtoComponent>("پیوست کارشناس", parameters: parameters);
+
+    }
+    async Task CallBackAttachedto()
+    {
+       await modal.HideAsync();
+        toastService.Notify(new ToastMessage(ToastType.Success, "کارشناس جدید به این گفتگو پیوست"));
+    }
     async Task OpenChat()
     {
         if (CurrentUser.Role == "Company" || CurrentUser.Role == "Exper" && ChatCurrent.ExperID==CurrentUser.ExperID)