diff --git a/model/dataset.py b/model/dataset.py
index f3cc897..ef58956 100644
--- a/model/dataset.py
+++ b/model/dataset.py
@@ -80,18 +80,18 @@ class SFTDataset(Dataset):
         #
         sample = self.df.iloc[index]
         history = self.safe_eval(sample['history'])
-        q = sample['q']
-        a = sample['a']
+        q = str(sample['q'])
+        a = str(sample['a'])
 
         messages = []
         for history_message in history:
             if len(history_message) <= 1:
                 continue
             messages.append(
-                {"role": 'user', "content": history_message[0][:self.max_length // 2]}
+                {"role": 'user', "content": str(history_message[0])[:self.max_length // 2]}
             )
             messages.append(
-                {"role": 'assistant', "content": history_message[1][:self.max_length // 2]}
+                {"role": 'assistant', "content": str(history_message[1])[:self.max_length // 2]}
             )
 
         messages += [