My smush stopped and don't start back

Hello,

I launched the Smush of all my pictures in the media library (46472 pictures) and i had to left, so i closed the page, as it is said in the instructions, to restart later.

Except that, it's blocked on 4170 of 46472. And when I click again on the "Bulk Smush now" button, it seems working but the counter doesn't change, it stays on 4170. I waited for an hour, and it didn't move. Can you help me please ? Thanks