04 Mercury Grand Marquis GS won't start

I have a 04 Mercury Grand Marquis GS with 94k on
it ran like a top with zero issues a month ago it
would not start so I replaced the starter and it
started just fine then my shifter cable broke so I
replaced the shifter cable and took it for a test
drive I had first second neutral reverse and when I
put it in park the reverse lights came on simple
linkage adjustment I assume when I went out to
adjust the linkage the car will not start the
alternator is good the battery is good the battery
connections are good the starter is brand new
when I turn the key all it will do is lock and unlock
the doors and that is it any help would be greatly
appreciated