diff --git a/src/Infrastructure/BotSharp.Abstraction/Messaging/Models/RichContent/RichContent.cs b/src/Infrastructure/BotSharp.Abstraction/Messaging/Models/RichContent/RichContent.cs
index 95f4e6e9..6ba617e7 100644
--- a/src/Infrastructure/BotSharp.Abstraction/Messaging/Models/RichContent/RichContent.cs
+++ b/src/Infrastructure/BotSharp.Abstraction/Messaging/Models/RichContent/RichContent.cs
@@ -10,6 +10,12 @@ public class RichContent<T> where T : IRichMessage
     public string MessagingType => "RESPONSE";
     public T Message { get; set; }
 
+    /// <summary>
+    /// If true, UI component will populate the replyMessage when sending back user message.
+    /// </summary>
+    [JsonPropertyName("fill_postback")]
+    public bool FillPostback { get; set; }
+
     public RichContent()
     {
         
diff --git a/tests/BotSharp.Plugin.PizzaBot/Functions/GetPizzaTypesFn.cs b/tests/BotSharp.Plugin.PizzaBot/Functions/GetPizzaTypesFn.cs
index ca348191..1842f557 100644
--- a/tests/BotSharp.Plugin.PizzaBot/Functions/GetPizzaTypesFn.cs
+++ b/tests/BotSharp.Plugin.PizzaBot/Functions/GetPizzaTypesFn.cs
@@ -34,6 +34,7 @@ public class GetPizzaTypesFn : IFunctionCallback
             {
                 Id = states.GetConversationId()
             },
+            FillPostback = true,
             Message = new ButtonTemplateMessage
             {
                 Text = "Please select a pizza type",