Update app.py

app.py

@@ -62,7 +62,7 @@ def get_vectorstore(chunks):
 
 # Create a conversational chain
 def get_conversationchain(vectorstore):
-    llm = ChatOpenAI(temperature=0.4, model_name='gpt-4')
+    llm = ChatOpenAI(temperature=0.4, model_name='gpt-4o-mini')
     memory = ConversationBufferMemory(memory_key='chat_history', return_messages=True)
     return ConversationalRetrievalChain.from_llm(
         llm=llm,