I lost my car key on a train.?

You need to list the make, model and year. There are too many key systems to list.

Key point is the anti-theft or interlock process. Most newer cars the key has a chip in it, so that has to be programmed by the dealer or some makes a locksmith may have the software.

Hi No time to be digging deep and getting a programmed key at the cars dealer.

Just about any locksmith should be able to do this for you.

The dealer could do it, but they likely wont if you don't buy the part from them.