Chrysler yr 2000, 300M with 200,000 miles won't start

I have been having problem starting the car for months now. At first, it started fine but when I stopped it will not re-start for 30 minutes. I took to the dealer to do a complete diagnostic and he said

'everything is fine. The problem re-occurred a month later with the same behavior. It happenned a couple of time but NOW it will not sart at all. I tried jumpin the battery, after few mintes the car stopped. Any suggestion PLEAAAAASE!!!

You’re going to have to determine whether the problem is fuel or spark related. Without knowing that, the number of possibilities go way up.

Either remove a plug wire, insert an old spark plug, ground the threaded shank of the plug, and note if there is a spark while cranking the engine over.
You could also spray a shot of aerosol carburetor cleaner into the intake through a vacuum line. Crank it over and if it starts and runs briefly (a few seconds) then it’s probably fuel related.

If it’s fuel related and if the fuel pump has never been replaced then that is more than likely where the problem is.
If the fuel filter has not been changed on a regular basis the chances of the problem being the pump goes way up as a clogged filter may allow the car to run fine and yet it will be death on a fuel pump.

What do you mean by WON’T START?? Will the car turn over?? Little more detail please.

Thank you for your suggestions. Since I do not know much about cars, I am towing it to the dealer to check those parts. The reason my asking is to have an idea of what might be the cause before taking it again to the dealer since he did not find any problems when I took to him for checkout when the problem first occurred. Now it is getting works, hopefully they will be able to fix it.
Thanks

What I meant by “car will not start” is the engine will not start when I turned the key in the ignition.

Quote you, “I tried jumpin the battery, after a few minuets, the car stopped.” Doesn’t this mean that the car started and ran for a few minuets? I don’t know why the dealer’s mechanics won’t, or can’t, troubleshoot this. If the vehicle is out of warranty, send it to an independent shop. I’m sure that THERE you’ll get more than just a shrug of the shoulders.

I hate to act like this is true but the car is only good for body parts now. @00,000 is not as far as a car can go but it could be the case here. If I had that model with those miles, I wouldn’t keep it. Your car will shart soon.