I'm assuming the case wasn't lubed properly. But this has happened. .223 Lyman die. and it won't come out.
He won't be able to pull the decapping stem out because the neck of the case is up in the die where it's sized down smaller than the expander ball. He'll need a stuck case remover.You may be able to use something like penitrating oil, take the decapper out, and use a pin punch and small hammer to punch it out from the top end. Or maybe put the shell bottom in a vise and pull it out that way. A little heat might work to but you dont wreck the die by warping it.
Me too but, I must have let the pad get too dry and stuck 3 cases, dopey me. Since then I got a new pad, actually just turned the old one over, presenting a nearly new side. No difficulties since.Since I have used an RCBS lube pad for 45 years without a stuck case, I'll just keep doing what works.
PS: lube sprays MUST be given time to let solvents evaporate.