diff --git a/rag/llm/embedding_model.py b/rag/llm/embedding_model.py
index 2ab95b337..785650a57 100644
--- a/rag/llm/embedding_model.py
+++ b/rag/llm/embedding_model.py
@@ -61,11 +61,11 @@ class DefaultEmbedding(Base):
         ^_-
 
         """
-        if not settings.LIGHTEN and not DefaultEmbedding._model:
+        if not settings.LIGHTEN:
             with DefaultEmbedding._model_lock:
                 from FlagEmbedding import FlagModel
                 import torch
-                if not DefaultEmbedding._model:
+                if not DefaultEmbedding._model or model_name != DefaultEmbedding._model_name:
                     try:
                         DefaultEmbedding._model = FlagModel(os.path.join(get_home_cache_dir(), re.sub(r"^[a-zA-Z0-9]+/", "", model_name)),
                                                             query_instruction_for_retrieval="为这个句子生成表示以用于检索相关文章：",
@@ -261,7 +261,7 @@ class FastEmbed(DefaultEmbedding):
             threads: int | None = None,
             **kwargs,
     ):
-        if not settings.LIGHTEN and not FastEmbed._model:
+        if not settings.LIGHTEN:
             with FastEmbed._model_lock:
                 from fastembed import TextEmbedding
                 if not DefaultEmbedding._model or model_name != DefaultEmbedding._model_name: