ok i think i discovered what happened and i didn't khew about it.
So i found in another corner of a map a enemy called "lost Hunter, and when i got near them, i don't khow if i pressed the lock on to try to talk or was automaticlly, i got my echoes back!
so it was not the same enemy, it was literally another hunter who saw my stuff and got it!
Thanks Eyesocket and... Vriska for helping me out (the last one for not thorwing me over a cliff i guess)