correct defect in retry when no agent

app.py

@@ -1396,7 +1396,10 @@ def retry(history3):
     yield history3
     
     try:
-        response = agent.run(message)
+        if agent is not None:
+            response = agent.run(message)
+        elif agent is None:
+            response = asyncio.run(start_playwright(message))
         time.sleep(0.1)
         history3 = history3 + [(None, response)]
         print ("response of chatbot:", response)
@@ -1414,7 +1417,7 @@ def retry(history3):
             print("No need to add file in chatbot")        
 
     except Exception as e:
-        print("chathmi3 error:", e)      
+        print("Retry error:", e)      
     # yield chathmi3(last_request, chatbot_history)
 
 def display_input(message, history2):