diff --git a/libs/ibm/langchain_ibm/chat_models.py b/libs/ibm/langchain_ibm/chat_models.py
index 64b3fd7..bfad13c 100644
--- a/libs/ibm/langchain_ibm/chat_models.py
+++ b/libs/ibm/langchain_ibm/chat_models.py
@@ -630,7 +630,7 @@ def _create_message_dicts(
         return message_dicts, params
 
     def _create_chat_result(
-        self, response: Union[dict], generation_info: Optional[Dict] = None
+        self, response: dict, generation_info: Optional[Dict] = None
     ) -> ChatResult:
         generations = []