I got success message for set params, but it did not reflect on my device. What may have happened?

The device may have disconnected from the network. Due to the MQTT keep-alive behaviour, the backend can take up to 180 seconds to detect that a device has gone offline. During this window, the backend still considers the device online and reports success when you set parameters—even if the message never reached the device. Once the device reconnects, it will sync with the cloud and reflect the last known state. If the parameter change was lost, set it again when the device is back online.