The app does not recognise the speaker in iOS 13

After updating to iOS 13, you will need to allow the app to access Bluetooth.

To do so, in your iOS Settings, go to your speaker’s app settings and turn on the Bluetooth access.

In case you have installed the app after the iOS update, you will be prompted with a message requesting Bluetooth access for the app. In this case, just click on “OK” to give access.