diff --git a/llmebench/models/FastChat.py b/llmebench/models/FastChat.py
index 7aa45668..52579352 100644
--- a/llmebench/models/FastChat.py
+++ b/llmebench/models/FastChat.py
@@ -5,18 +5,18 @@
 
 class FastChatModel(OpenAIModel):
     def __init__(self, api_base=None, api_key=None, model_name=None, **kwargs):
-        self.api_base = api_base or os.getenv("OPENAI_API_BASE")
-        self.api_key = api_key or os.getenv("OPENAI_API_KEY")
-        self.model_name = model_name or os.getenv("OPENAI_MODEL")
-        if self.api_base is None:
+        api_base = api_base or os.getenv("OPENAI_API_BASE")
+        api_key = api_key or os.getenv("OPENAI_API_KEY")
+        model_name = model_name or os.getenv("OPENAI_MODEL")
+        if api_base is None:
             raise Exception(
                 "API url must be provided as model config or environment variable (`OPENAI_API_BASE`)"
             )
-        if self.api_key is None:
+        if api_key is None:
             raise Exception(
                 "API url must be provided as model config or environment variable (`OPENAI_API_KEY`)"
             )
-        if self.model_name is None:
+        if model_name is None:
             raise Exception(
                 "API url must be provided as model config or environment variable (`OPENAI_MODEL`)"
             )