Happened to me as well. Got 3 .45 UMP mags a week ago; FedEx guy dropped ‘em and ran off.
2 PSP mags today, same thing as OP. FedEx guy says he’s tired of this $hit and just handed me the package.
Maybe it’s because they’re for a pistol. In the view of our esteamed overlords, you need ID for those evil pistol mags, but feel free to go and shoot up the neighborhood with your 25 round subgun mags??? We don’t need no stinkin’ ID!