If your Mews Terminal shows a "Not connected," "Network not connected," or "Disconnected" message, since your terminal connects to the internet through Wi-Fi i.e., via a wireless network, you need to check your Wi-Fi network settings. Note: Mews does not support 3G or 4G network.
You can learn more about troubleshooting Mews Terminals here and in the troubleshooting section here.