Mini Parking Sensors

[Crompy62]

Hi I'm looking for help my wife's 2016 MIni Cooper parking sensors have stopped making an audible sound. The visual from the camera still seems to show the green to red colours. I've checked the fuse (55) and it looks fine.

I think the sensors are working as they show on the screen but there is no sound and i'm now at a loss and welcome any help.