recovering file that's been deleted for the second time

as I was making some room for my external hard drive, I accidentally deleted some important files, I instantly downloaded recuva, and successfully recovered it. So I went back to cleaning up my drive, but then stupidly, I deleted those files again. no worries, I thought, I just ran recuva again, but none of the files showed up. So I tried some other tools too, but didn't really work out. is this unrecoverable?