Make sure you are using the latest Konftel Unite app before you upgrade the Konftel 300IPx. If you upgrade from 2.7.11 (and earlier) and you have an iOS device (iPhone/iPad), which is already paired to Konftel 300IPx, you will need to remove the pairing in your iOS Bluetooth settings before you can use Konftel Unite again. To remove the pairing on iOS, go to Settings > Bluetooth, select Konftel 300IPx and then click on “Forget this device”. After you have removed the pairing you may open Konftel Unite app and connect to Konftel 300IPx.