diff --git a/tests/gateway/test_teams.py b/tests/gateway/test_teams.py
index 7a035142..2100a264 100644
--- a/tests/gateway/test_teams.py
+++ b/tests/gateway/test_teams.py
@@ -397,13 +397,22 @@ class TestTeamsSend:
         assert "Network error" in result.error
 
     @pytest.mark.asyncio
-    async def test_send_typing(self):
+    async def test_send_typing(self, monkeypatch):
         adapter = TeamsAdapter(_make_config(
             client_id="id", client_secret="secret", tenant_id="tenant",
         ))
         mock_app = MagicMock()
         mock_app.send = AsyncMock()
         adapter._app = mock_app
+        # The adapter module imports TypingActivityInput at load time; if
+        # the real microsoft_teams package isn'"'"'t installed, that local
+        # binding is None even though the test fixture registers a mock
+        # in sys.modules. Force a non-None local binding so the call to
+        # TypingActivityInput() inside send_typing succeeds and we actually
+        # reach self._app.send.
+        class _StubTypingActivityInput:
+            pass
+        monkeypatch.setattr(_teams_mod, "TypingActivityInput", _StubTypingActivityInput)
 
         await adapter.send_typing("conv-id")
         mock_app.send.assert_awaited_once()