When the temperature and humidity monitor is not paired, you can enter pairing mode by reassembling the battery. When the temperature and humidity monitor already has a pairing record, you need to unpair the device on APPs, then press and hold the pairing button on the device for 5 seconds. When you see the signal sign on the screen is flashing, the temperature and humidity monitor has entered pairing mode, and you can operate the app to connect to the RBF network. Another method is to scan the QR code on the temperature and humidity monitor to connect to the network.