Wont accept my .wav files

I got this nasty virus crypt which turned all my wave files into cryptz files, so fortunately I had backed up all my wave files so I re-put all my wave files from my back up.

Now most of them work no problem but I have a dozen or so that don’t . When I try to force it on with the find my file it keeps tell me " invalid or unsupported file"

Why ? It’s the same wav file
How can I make this work