diff --git a/devchat/openai/openai_prompt.py b/devchat/openai/openai_prompt.py
index b5fedf61..e1ed1b97 100644
--- a/devchat/openai/openai_prompt.py
+++ b/devchat/openai/openai_prompt.py
@@ -90,10 +90,11 @@ def set_response(self, response_str: str):
         self._request_tokens = response_data['usage']['prompt_tokens']
         self._response_tokens = response_data['usage']['completion_tokens']
 
-        self._new_messages['response'] = {
-            choice['index']: OpenAIMessage(**choice['message'])
-            for choice in response_data['choices']
-        }
+        for choice in response_data['choices']:
+            index = choice['index']
+            if index >= len(self.response):
+                self.response.extend([None] * (index - len(self.response) + 1))
+            self.response[index] = OpenAIMessage(**choice['message'])
         self.set_hash()
 
     def append_response(self, delta_str: str) -> str:
@@ -116,7 +117,10 @@ def append_response(self, delta_str: str) -> str:
             delta = choice['delta']
             index = choice['index']
 
-            if index not in self.response:
+            if index >= len(self.response):
+                self.response.extend([None] * (index - len(self.response) + 1))
+
+            if not self.response[index]:
                 self.response[index] = OpenAIMessage(**delta)
                 if index == 0:
                     delta_content = self.formatted_header()
diff --git a/devchat/prompt.py b/devchat/prompt.py
index ee224d8b..72c733d9 100644
--- a/devchat/prompt.py
+++ b/devchat/prompt.py
@@ -36,7 +36,7 @@ class Prompt(ABC):
         Message.INSTRUCT: [],
         'request': None,
         Message.CONTEXT: [],
-        'response': {}
+        'response': []
     })
     _history_messages: Dict[str, Message] = field(default_factory=lambda: {
         Message.CONTEXT: [],
@@ -73,7 +73,7 @@ def request(self) -> Message:
         return self._new_messages['request']
 
     @property
-    def response(self) -> Dict[int, Message]:
+    def response(self) -> List[Message]:
         return self._new_messages['response']
 
     @property