diff --git a/tuning/sft_trainer.py b/tuning/sft_trainer.py
index b3e28f686..1c4fdb9a6 100644
--- a/tuning/sft_trainer.py
+++ b/tuning/sft_trainer.py
@@ -232,6 +232,7 @@ def train(
         ),
         cache_dir=train_args.cache_dir,
         use_fast=True,
+        legacy=True,
     )
 
     # Calculate and save additional metrics to track later.