Update app.py

app.py

@@ -219,7 +219,7 @@ def chat(selected_option=None, radio_score=None, url_params=None):
     history = chat_history + history
     chatbot.value = history
     chatbot.update(value=history)
-
+    client = None
     return history
 
 
@@ -250,7 +250,8 @@ def update_target_website():
     global chat_history
     global client
     global name
-
+    
+    client = None
     name = "no username"
 
     chat_history = [