Update app.py

app.py

@@ -8,7 +8,7 @@ client = Client()
 def chat_with_gpt(user_input):
     try:
         response = client.chat.completions.create(
-            model="gpt-4-o",
+            model="gpt-4o",
             messages=[{"role": "user", "content": user_input}]
         )
         return response.choices[0].message.content