diff --git a/sm2gen.py b/sm2gen.py
index 44691e0..1976023 100644
--- a/sm2gen.py
+++ b/sm2gen.py
@@ -314,11 +314,11 @@ def check_file_version(filename):
         # Convert the string timestamp to a datetime object
         file_timestamp = datetime.strptime(timestamp_str, '%Y-%m-%d %H:%M:%S')
 
-        # Get the last modified time of the file
-        file_modified_time = datetime.fromtimestamp(os.path.getmtime(filename))
+        # Get the last modified time of the file, ignoring milliseconds
+        file_modified_time = datetime.fromtimestamp(os.path.getmtime(filename)).replace(microsecond=0)
 
         # Compare the timestamps
-        if file_modified_time > file_timestamp:
+        if file_modified_time > (file_timestamp):
             return f"{filename}.new"
         else:
             return filename