diff --git a/main.py b/main.py
index 3012caeb..f330a166 100644
--- a/main.py
+++ b/main.py
@@ -3,7 +3,7 @@
 from streamlit_chat import message
 import faiss
 from langchain import OpenAI
-from langchain.chains import VectorDBQAWithSourcesChain
+from langchain.chains import RetrievalQAWithSourcesChain
 import pickle
 
 # Load the LangChain.
@@ -13,7 +13,7 @@
     store = pickle.load(f)
 
 store.index = index
-chain = VectorDBQAWithSourcesChain.from_llm(llm=OpenAI(temperature=0), vectorstore=store)
+chain = RetrievalQAWithSourcesChain.from_chain_type(OpenAI(temperature=0), chain_type="stuff", retriever=store.as_retriever())
 
 
 # From here down is all the StreamLit UI.
diff --git a/qa.py b/qa.py
index 9152cc15..63e1614c 100644
--- a/qa.py
+++ b/qa.py
@@ -1,7 +1,7 @@
 """Ask a question to the notion database."""
 import faiss
 from langchain import OpenAI
-from langchain.chains import VectorDBQAWithSourcesChain
+from langchain.chains import RetrievalQAWithSourcesChain
 import pickle
 import argparse
 
@@ -16,7 +16,7 @@
     store = pickle.load(f)
 
 store.index = index
-chain = VectorDBQAWithSourcesChain.from_llm(llm=OpenAI(temperature=0), vectorstore=store)
+chain = RetrievalQAWithSourcesChain.from_chain_type(OpenAI(temperature=0), chain_type="stuff", retriever=store.as_retriever())
 result = chain({"question": args.question})
 print(f"Answer: {result['answer']}")
 print(f"Sources: {result['sources']}")
diff --git a/requirements.txt b/requirements.txt
index c99f9572..21ce5d4e 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,5 +1,6 @@
-langchain==0.0.58
+langchain==0.0.126
 openai
 faiss-cpu
 streamlit
 streamlit-chat
+tiktoken