diff --git a/backend/apps/ollama/main.py b/backend/apps/ollama/main.py
index 19d914c4b..79a2773ba 100644
--- a/backend/apps/ollama/main.py
+++ b/backend/apps/ollama/main.py
@@ -729,7 +729,7 @@ async def generate_chat_completion(
     payload = {
         **form_data.model_dump(exclude_none=True, exclude=["metadata"]),
     }
-    payload.pop("metadata")
+    payload.pop("metadata", None)
 
     model_id = form_data.model
     model_info = Models.get_model_by_id(model_id)
@@ -788,7 +788,7 @@ async def generate_openai_chat_completion(
 ):
     completion_form = OpenAIChatCompletionForm(**form_data)
     payload = {**completion_form.model_dump(exclude_none=True, exclude=["metadata"])}
-    payload.pop("metadata")
+    payload.pop("metadata", None)
 
     model_id = completion_form.model
     model_info = Models.get_model_by_id(model_id)
diff --git a/backend/apps/openai/main.py b/backend/apps/openai/main.py
index 1313d2091..44b3151e0 100644
--- a/backend/apps/openai/main.py
+++ b/backend/apps/openai/main.py
@@ -359,7 +359,7 @@ async def generate_chat_completion(
 ):
     idx = 0
     payload = {**form_data}
-    payload.pop("metadata")
+    payload.pop("metadata", None)
 
     model_id = form_data.get("model")
     model_info = Models.get_model_by_id(model_id)