While driving on the highway my van stalled. Once on the side of the road, I tried to restart and no joy. All indicators and lights came on but when I turned the key nothing happened. I jiggled he key and checked the transmission was in park. Once the vehicle was towed and arrived at the shop it started fine. No codes or indications of anything wrong. Since then it has done it twice more, but started right away. Please help.
That sounds to me like an ignition switch that is failing. Do you have a lot of keys that share the same keyring as the key for the ignition? You might start by removing as much weight as you can from the keyring.
If you have a heavy key ring, and that doesn't reliably fix it, then look into the cost of a new ignition switch. Intermittent problems like this can be very hard to diagnose and a car that randomly stalls can be quite dangerous.
Take a look at the answers to this question – inspired by your question – to see if any of them might fit your situation.
Once upon a time, I had a car that did this. Over and over.
The connector for the wiring harness that ran the fuel pump worked loose. The car stopped. The bouncing involved in towing the car to the shop jostled it back into place. The car worked. We eventually diagnosed it by driving it over a street with potholes.