From f91a55c97c2787dc19406ba7cb5438e4b5a01c93 Mon Sep 17 00:00:00 2001
From: filipi87 <filipi87@gmail.com>
Date: Thu, 7 May 2026 11:32:48 -0300
Subject: [PATCH] Changelog entry for the fix.

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 changelog/4440.fixed.md | 1 +
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+- Fixed a race condition in the Daily transport that caused `AttributeError: 'NoneType' object has no attribute 'send_app_message'` when tearing down a pipeline. Both `DailyInputTransport` and `DailyOutputTransport` share the same `DailyTransportClient` and both call `cleanup()`, which was releasing the underlying `CallClient` on the first call — leaving the second caller with a `None` client.