Arrived and found that the upstairs master bathroom shower is constantly dripping and won’t turn off. This is the only faucet in the home that is dripping. House water pressure is currently at 75psi which is indicating that the pressure reducing valve located in garage beside water heater is old and starting to fail. Highly recommend replacing prv as soon as possible. Advised customer of possible issues that could occur if the high water pressure is not addressed soon. Customer understands high pressure can damage plumbing parts/fixtures and agreed for me to go ahead and replace the shower cartridge now and he will call us back asap to replace the pressure reducing valve. Installed new delta grey cartridge and is working properly and not dripping.