There are multiple things that could cause this problem, but if everything else seems to work fine, a good place to check would be the transmission and the shifter. Gears in the transmission could be blown and may not catch when you try to shift.
need more info.year,model.
A seized up transmission can cause a Volkswagen Golf with an automatic transmission to not shift and racing RMPs after second. A worn gear can also prevent shifting.
try the shift sensor on the side of tranny
My 1998 Nissan sentra wony shift into high gear
the sunshell gear is stripped out
Sometimes when used to driving manual transmissions, we forget to press the brake pedal to release the safety so we can shift the automatic into gear. It will not shift out of park unless you do this.
You may have a broken transmission or be low on transmission fluid.
my 2001 ford windstar wont shift out of first gear.
A 93 Deville that wont shift from second gear has most likely got an internal transmission problem. Unless the linkage is mis-adjusted, then the problem is onside of the transmission.
could be the shifter linkage or cable itself also check fluid level if it is a automatic transmission or if it is a manual transmission could be clutch and throwout bearing
could be the modulator valve has went bad !
I know that my 1995 XLT has a brake interlock switch, that doesn"t allow my automatic transmission to shift out of park into gear unless the brake pedal is depressed - I don't know if that is what your problem is.