Update app.py

app.py

@@ -315,7 +315,10 @@ def create_qa_chain(vectorstore, llm):
         llm=llm,
         retriever=retriever,
         chain_type="stuff",
-        chain_type_kwargs={"prompt": qa_prompt}
+        chain_type_kwargs={
+            "prompt": qa_prompt,
+            "document_variable_name": "context"  # Match the variable name in the prompt
+        }
     )
     return qa_chain