Flash exif not showing

Hi,
I’ve recently changed my camera. With my new one, the Flash exif returns a blank field. (It was working fine with the old camera).
On the Windows file properties, I’ve seen that the old camera returns “no flash, mandatory” and the new camera “no flash”. There is not the “mandatory” with the new one… and your plugin doesn’t display “yes” or “no”…

Any idea about this problem ?
Many thanks !

Bertrand