diff --git a/api/ragflow_server.py b/api/ragflow_server.py
index 52e565b48..d98f8a264 100644
--- a/api/ragflow_server.py
+++ b/api/ragflow_server.py
@@ -61,6 +61,8 @@ def update_progress():
             stop_event.wait(6)
         except Exception:
             logging.exception("update_progress exception")
+            if redis_lock.acquired:
+                redis_lock.release()
 
 def signal_handler(sig, frame):
     logging.info("Received interrupt signal, shutting down...")