IoT客户端on_message_received未触发接收C2D消息

已按微软文档实现云到设备（C2D）消息功能：

• 后端通过IoTHubRegistryManager发送C2D消息正常，运行后在IoT Hub门户可确认目标设备的C2D消息队列数为1。
• 设备端使用IoTHubModuleClient初始化连接，device_twin_patch_handler（孪生更新）、connection_change_handler（连接状态变更）均可正常触发，但绑定到on_message_received的receive_message_handler从未被调用，已确认消息发送到了当前连接的设备。

设备端简化代码如下：

class RunnerClass:
    def __init__(self):
        self.iot_client: IoTHubModuleClient

    async def device_twin_patch_handler(self, patch: dict) -> None:
        # 孪生更新时触发（正常工作）
        logging.info("Handle incoming patch.")

    async def connection_change_handler(self) -> None:
        # 连接状态变更时触发（正常工作）
        logging.info("Connection change detected...")

    async def receive_message_handler(self, message: Message) -> None:
        # C2D消息进入设备队列时未触发此方法
        logging.info("Received optimization response:")
        for property in vars(message).items():
            logging.info(f"\t{property}")

    async def create_iot_client(self) -> None:
        self.iot_client: IoTHubModuleClient = IoTHubModuleClient.create_from_edge_environment()
        await self.iot_client.connect()

        self.iot_client.on_message_received = self.receive_message_handler
        self.iot_client.on_twin_desired_properties_patch_received = self.device_twin_patch_handler
        self.iot_client.on_connection_state_change = self.connection_change_handler

是否遗漏了某些配置？使用的是标准层IoT Hub。

内容的提问来源于stack exchange，提问作者poklaassen