So I woke up to find the lamp in the lounge was on. Checked the Smartthings app to find it was switched on by motion. It appears the motion sensor has been detecting motion all night, and as a result the lounge lamp has been switching on & off all night!
The sensor is on the wall in the lounge, and has been all year. Battery level shows good. Windows shut. No animals.
Any ideas? I assume faulty sensor?