the vehicle may appear to be all the way in park, but the lever that releases the key may not disengage from the ignition. Sometimes, pulling the lever toward you, shoving hard to the left while firmly pushing the shifter back towards the instrument cluster will make it possible to get it out. Also, holding it there and wiggling it back and forth while trying to turn the key may free it up. There is something that needs to be adjusted or replaced, but this could help get the key out at the time.
I had the same problem with my husbands 1990Ford F250. I couldn't remove the key no matter how much I fiddled with it. It was suggested to me by a locksmith that I try graphite in a squirtable tube, which I did. After a little bit of jiggling it came out. However I have not been game to put the key back in as yet!