diff --git a/posts.py b/posts.py
index 6e275d45f..5b54e0c8c 100644
--- a/posts.py
+++ b/posts.py
@@ -3362,7 +3362,7 @@ def expireCache(baseDir: str, personCache: {},
     while True:
         # once per day
         time.sleep(60 * 60 * 24)
-        expirePersonCache(baseDir, personCache)
+        expirePersonCache(personCache)
         archivePosts(baseDir, httpPrefix, archiveDir, recentPostsCache,
                      maxPostsInBox)