diff --git a/setup.py b/setup.py
index 23936eb..f3351c8 100644
--- a/setup.py
+++ b/setup.py
@@ -4,7 +4,7 @@
 
 setup(
     name="modelmerge",
-    version="0.5.0",
+    version="0.5.1",
     description="modelmerge is a multi-large language model API aggregator.",
     long_description=Path.open(Path("README.md"), encoding="utf-8").read(),
     long_description_content_type="text/markdown",
diff --git a/src/ModelMerge/models/chatgpt.py b/src/ModelMerge/models/chatgpt.py
index ff118ae..2adc30b 100644
--- a/src/ModelMerge/models/chatgpt.py
+++ b/src/ModelMerge/models/chatgpt.py
@@ -353,8 +353,11 @@ def ask_stream(
                 return
             # print("response.text", response.text)
             if response.status_code == 400:
-                del json_post["function_call"]
-                del json_post["functions"]
+                print("response.text", response.text)
+                if "function_call" in json_post:
+                    del json_post["function_call"]
+                if "functions" in json_post:
+                    del json_post["functions"]
                 continue
             if response.status_code == 200:
                 break