diff --git a/text/japanese_bert.py b/text/japanese_bert.py
index 7e528e9..2974c76 100644
--- a/text/japanese_bert.py
+++ b/text/japanese_bert.py
@@ -49,7 +49,7 @@ def get_bert_feature(
             style_res = torch.cat(style_res["hidden_states"][-3:-2], -1)[0].cpu()
             style_res_mean = style_res.mean(0)
 
-    assert len(word2ph) == len(text) + 2
+    assert len(word2ph) == len(text) + 2, text
     word2phone = word2ph
     phone_level_feature = []
     for i in range(len(word2phone)):
diff --git a/webui_train.py b/webui_train.py
index 7b631a7..7f1be90 100644
--- a/webui_train.py
+++ b/webui_train.py
@@ -65,6 +65,7 @@ def initialize(model_name, batch_size, epochs, save_every_steps, bf16_run):
         shutil.copytree(
             src=model_path,
             dst=os.path.join(dataset_path, "models_backup"),
+            dirs_exist_ok=True,
         )
         shutil.rmtree(model_path)
     try: