Don’t worry, contact the support and they will take the file down. And the user also. I remember that few weeks ago somebody did this same to Mockups Zone, the situation was quite similar to yours. The file was deleted in next days.
This is pretty bad situation if someone steal not just the file, but all identity.
Good Luck, I love your work.
we have seen even worst lol , some guys duplicating GR’s site, having fake account for the real authors and selling aall for themselves … cannot get worst than this indeed …