diff --git a/src/utils/seq2seq.py b/src/utils/seq2seq.py
index f9a9dc6b..cfa637d7 100644
--- a/src/utils/seq2seq.py
+++ b/src/utils/seq2seq.py
@@ -79,11 +79,13 @@ class Seq2SeqPeftTrainer(PeftTrainer):
 
         Subclass and override to inject custom behavior.
         """
-        input_ids = inputs["input_ids"]
+        prompt_len, label_len = inputs["input_ids"].size(-1), inputs["labels"].size(-1)
+        inputs["labels"] = torch.cat((inputs["labels"], torch.zeros_like(inputs["input_ids"])[:, label_len:]), dim=-1)
         loss, generated_tokens, labels = super().prediction_step(
             model, inputs, prediction_loss_only=prediction_loss_only, ignore_keys=ignore_keys
         )
-        generated_tokens = generated_tokens[:, input_ids.size(-1):] if generated_tokens is not None else None
+        generated_tokens = generated_tokens[:, prompt_len:] if generated_tokens is not None else None
+
         return (loss, generated_tokens, labels)
 
     def save_predictions(