Get a 1/4-20 tap and matching drill.
Drill out the primer pocket and tap the hole.
Get a 1/4-20 bolt, washer, and a 3/8 drive socket that will clear the cartridge base, but rest on the bottom of the die (or on a lockring screwed all the way down to the bottom of the die).
Insert bolt through washer and drive end of socket, then thread into tapped hole in stuck case.
Tighten bolt, and it should pull the case out of the die.
Use more/better lube on the case to prevent this in the future.
Andy