Make sure that your Bluetooth is turned ON, so that you can use the Beacon.
If your Bluetooth is ON but the Beacon is still not working, try waiting a bit for your device to respond. There’s a possibility that there is some time lag in the transmission.
It’s also possible that your phone case is blocking the transmission. You can try removing it.
In addition, even if Bluetooth is ON for iOS, if [Location Services] for the app are not set to [Always Allow], the Beacon will not respond.
Other than that, Bluetooth uses the 2.4GHz band. so several factors due to the presence of objects using the same band could interfere with its operations.
Other Bluetooth devices
Wi-Fi base stations set to 2.4 GHz band
Other wireless devices using 2.4GHz
If any of the above objects are present nearby, please change their settings or locations.