Car not starting

I have a 01 Chrylser town & Country I took the car to the dealer and told service manager car want start they replaced fuel pump fuel filter changed oil put gaskets on it tuned it up after all that drove car away a week later car still want start, so I put new fuel pump on changed fuel filter again now car will start some time when it does start if you put it in reverse engine shuts off it will run if you put it in drive but not in reverse