Just replied on other posting, but also make sure the transmitter is securely snapped in both sides. Pinch it with your fingers to make sure. Try again in the morning - let it wet overnight. Leave everything in and the transmitter snapped in and the receiver close by. I do way better with mine if I insert at bedtime, and start in the am - even with the G4 - otherwise I tend to get a lot of weird readings the first day.