diff --git a/src/litserve/server.py b/src/litserve/server.py
index f756f4fb..feb44e26 100644
--- a/src/litserve/server.py
+++ b/src/litserve/server.py
@@ -251,7 +251,7 @@ async def lifespan(self, app: FastAPI):
                 "the LitServer class to initialize the response queues."
             )
 
-        response_queue = self.response_queues[app.response_queue_id]
+        response_queue = self.response_queues[self.app.response_queue_id]
         response_executor = ThreadPoolExecutor(max_workers=len(self.inference_workers))
         future = response_queue_to_buffer(response_queue, self.response_buffer, self.stream, response_executor)
         task = loop.create_task(future)