You need to reset your sensor can.
1. Turn the power off by removing one battery.
2. Put your hand over the sensor for about one second until the LED light blinks once to indicate that the power and electronic memory are completely drained.
3. Turn the power back on by reinserting the battery removed.
4. The sensor can needs at least as few as five and as many as twenty cycles to get “up to speed” (you can consider the first 20 openings as the warm-up period).