Long ago when there was no facility for having smart cards as students or clerks, there were some blank spaces or balloons on the cards needed to be stamped to be accredited. What do/did you name those balloon like things? Accreditation area/space?
It would probably depend on the shape but I'd call it a "space", or a "box" (if it were square).
Remember - if you don't use correct capitalisation, punctuation and spacing, anything you write will be incorrect.