Balance 2 censor light flashing when everything's off

Hi everyone. So I got auto heart rate off, O2 off, sleep, stress off, sleep monitor off. And the green light is still beaming sometimes when I lift the watch a little bit. Not always just sometimes I would catch it being on. It's continuous and not blinking. The only thing I have on is active heart rate which tracks heart rate when you're doing a physical activity. But I'm talking about it flashing when I'm just sitting. Anyone know what could possibly be causing this?