diff --git a/sen2chain/time_series.py b/sen2chain/time_series.py
index 7f4fc9c1717cfc0b003e12bcabaead25da60d497..7f5beb04b5eba658101c51d33610c2e86732d8ba 100644
--- a/sen2chain/time_series.py
+++ b/sen2chain/time_series.py
@@ -203,5 +203,5 @@ class TimeSeries:
                 df_name,
                 self._date_min,
                 self._date_max)
-            df.sort_values(by=['fid', 'date']).to_csv(str(csv_path))
+            df.sort_values(by=['fid']).to_csv(str(csv_path))
             logger.info("exported to csv: {}".format(csv_path))