I take it is a 2.7tdv6 then as you have left the engine size fuel type out, we are not mind readers. Generally the aa rac green flag don't really understand these cars i see it on a day to day basis at work, you need correct diagnosis scanner, or get the aa landrover assist out to help read it. Then we can go further, it could be a seized engine, blocked turbos, battery fecked, starter fecked, blown fuses, snapped fuel pump belt, it could be anything you need to give more information and dtc readings