In Alert Mode you can control the alerts when device and phone app get disconnected. You can control the audio alerts from the physical device and notifications from your phone.
Step 1
Open the Nut app. Tap on 'Alert Mode' to go into the settings. Make sure it's turned on
Step 2
Turn "Device Alert" on and select the period that it'll be on for, as well as the duration.
Step 3
Turn "Phone Alert" on and select the sound the phone will make, as well as the duration.