Update app.py

app.py

@@ -32,14 +32,18 @@ def upload_pdf(pdf_file_path):
 def respond(message, chat_history):
     global qa_chain
     if qa_chain is None:
-        return message, chat_history + [[message, "⚠️ Please upload a PDF first."]]
+        return message, chat_history + [{"role": "assistant", "content": "⚠️ Please upload a PDF first."}]
+    
     try:
         result = qa_chain({"query": message})
         answer = result["result"]
-        chat_history.append((message, answer))
+        chat_history.append({"role": "user", "content": message})
+        chat_history.append({"role": "assistant", "content": answer})
         return "", chat_history
     except Exception as e:
-        return "", chat_history + [[message, f"❌ Error: {e}"]]
+        chat_history.append({"role": "user", "content": message})
+        chat_history.append({"role": "assistant", "content": f"❌ Error: {e}"})
+        return "", chat_history
 
 def create_interface():
     with gr.Blocks(css=css, theme="soft") as demo:
@@ -51,7 +55,7 @@ def create_interface():
         pdf_input = gr.File(label="Upload PDF", type="filepath", file_types=[".pdf"])
         status = gr.Markdown()
 
-        chatbot = gr.Chatbot(elem_id="chatbot", visible=False)
+        chatbot = gr.Chatbot(elem_id="chatbot", visible=False, type="messages")  # ✅ fixed type here
 
         examples = [
             "What are the admission requirements?",