15 feet should be more than far enough away. But you could try moving it further away. There isn't a light on in the boot or anything? Or door or bonnet not shut properly. Is the app reporting that all doors are closed etc?The garage are saying they can't find a parasitic drain even though the AA did. The 12 volt battery needs replacement but whether that was the cause seems moot. One idea I had was, could the proximity of the key fob be an issue. I have recently been keeping it in a hallway only about 15-20 feet from the car, I used to keep the fob in the kitchen maybe 40 feet away and in a RFID wallet which I stopped doing for no good reason. Maybe the garage has been keeping the fob well away from the car whilst they are testing it. Could this be an issue does anyone think?