Volvo V4 Bluetooth

Mine does the same thing with an iPhone every couple of months or so.

The only way I’ve found to fix it is to stop the truck. Unpair the phone from the truck and the truck from the phone. Isolate the truck with the switch behind your front offside wheel (for around 1 minute). Turn it back on again. Add / pair the phone with the truck and it should be good for a couple of months.