Check the power supply and the circuit breaker of your hot water heater. If the power is on and the breaker is not tripped, you can try resetting the thermostat or relighting the pilot light if you have a gas heater. If this doesn’t work or you are not comfortable doing them, you should call a professional water heater repair service in Las Vegas, such as Active Plumbing & Air Conditioning, to diagnose and fix your problem.