Arrived and found that the customer has had an increasing water bill for the last three months with no signs of a leak. Dye tested all three toilets and no leaks. Watched meter for several minutes and no indication of a leak. Checked pressure and turned on multiple faucets the pressure went from about 70 down to 20psi which indicates that the pressure reducing valve is failing, allowing excessive pressure into home at night. Replaced pressure reducing valve in garage. Set pressure to 65psi.