announcement update with emtpy tag

app/controllers/panel/announcement/back_end/bulletins_controller.rb

@@ -122,7 +122,7 @@ class Panel::Announcement::BackEnd::BulletinsController < OrbitBackendController
 
   def update
       @bulletin = Bulletin.find(params[:id])
-
+      params[:bulletin][:tag_ids] = (params[:bulletin][:tag_ids] ? params[:bulletin][:tag_ids] : [])
       delete_out_invalid_date_from_params
       respond_to do |format|
         if @bulletin.update_attributes(params[:bulletin])

app/views/panel/announcement/back_end/bulletins/_form.html.erb

@@ -100,7 +100,6 @@
           <% @tags.each do |tag| %>
             <label class="checkbox inline btn <%= 'active' if @bulletin.tag_ids.include?(tag.id) %>">
               <%= check_box_tag 'bulletin[tag_ids][]', tag.id, @bulletin.tag_ids.include?(tag.id) %> <%= tag.name %>
-              <%= hidden_field_tag 'bulletin[tag_ids][]', '' %>
             </label>
           <% end %>
         </div>