I recently purchased a 2011 Nissan Dualis 4D FWD manual with 180,000 km on the clock. It looks good, runs well, everything worked until suddenly, the central locking became unreliable. The spare integrated key fob would not work either. I replaced the battery in the key fob, but it still will not work. I tried over a period of time from many directions and distances, all the while studying the owner’s manual and following the instructions. Now the car cannot be reliably locked. Any advice?