diff --git a/libraries/botbuilder-core/botbuilder/core/turn_context.py b/libraries/botbuilder-core/botbuilder/core/turn_context.py
index 6c4a4eef3..852fd1f31 100644
--- a/libraries/botbuilder-core/botbuilder/core/turn_context.py
+++ b/libraries/botbuilder-core/botbuilder/core/turn_context.py
@@ -158,7 +158,7 @@ async def send_activity(
         activity_or_text: Union[Activity, str],
         speak: str = None,
         input_hint: str = None,
-    ) -> ResourceResponse:
+    ) -> Union[ResourceResponse, None]:
         """
         Sends a single activity or message to the user.
         :param activity_or_text: