diff --git a/server/apps/exam/views.py b/server/apps/exam/views.py
index 6eb6305..8ccf0a5 100644
--- a/server/apps/exam/views.py
+++ b/server/apps/exam/views.py
@@ -730,7 +730,7 @@ class ExamRecordViewSet(ListModelMixin, DestroyModelMixin, RetrieveModelMixin, G
 
 def acquire_lock(lock_name, timeout=60):
     identifier = str(uuid.uuid4())
-    lock = cache.set(lock_name, identifier, timeout=timeout, nx=True)
+    lock = cache.set(lock_name, identifier, timeout=timeout)
     return identifier if lock else None
 
 def release_lock(lock_name, identifier):