diff --git a/memos/commands.py b/memos/commands.py
index ddc1e99..8781315 100644
--- a/memos/commands.py
+++ b/memos/commands.py
@@ -48,7 +48,7 @@ def format_timestamp(timestamp):
     if isinstance(timestamp, str):
         return timestamp
     return (
-        datetime.fromtimestamp(timestamp, tz=timezone.utc)
+        datetime.fromtimestamp(timestamp)
         .replace(tzinfo=None)
         .isoformat()
     )