diff --git a/backend/open_webui/routers/retrieval.py b/backend/open_webui/routers/retrieval.py
index 5c7a323565..885f45d46a 100644
--- a/backend/open_webui/routers/retrieval.py
+++ b/backend/open_webui/routers/retrieval.py
@@ -1215,7 +1215,8 @@ async def update_rag_config(request: Request, form_data: ConfigForm, user=Depend
         else config.RAG_RERANKING_BATCH_SIZE
     )
 
-    log.info('Updating reranking model: %s to %s', config.RAG_RERANKING_MODEL, form_data.RAG_RERANKING_MODEL)
+    if form_data.RAG_RERANKING_MODEL is not None:
+        log.info('Updating reranking model: %s to %s', config.RAG_RERANKING_MODEL, form_data.RAG_RERANKING_MODEL)
     try:
         config.RAG_RERANKING_MODEL = (
             form_data.RAG_RERANKING_MODEL if form_data.RAG_RERANKING_MODEL is not None else config.RAG_RERANKING_MODEL