corrected case-sensitive filename

main.py

@@ -20,7 +20,7 @@ def main():
     if not os.path.exists("./default.sqlite"):
 
         documents = SimpleDirectoryReader(
-            input_files=["./raw_documents/HI_knowledge_base.pdf"]
+            input_files=["./raw_documents/HI_Knowledge_Base.pdf"]
         ).load_data()
 
         document = Document(text="\n\n".join([doc.text for doc in documents]))