Get rid of command line errors

Good afternoon, dear habrashabiteli and readers. For several days I have been tormented by automating the process of creating thumbnails from mp3.

Every day music is poured into a folder, after a certain time there is a check for the presence of this music in the folder, if the files exist, they are sent for cutting (mp3split), and then in lame . For now, the usual Windows command line is used. And here's the ill luck: after sending files to lame, with sadness in my eyes I get

"lfnfor"
, .
"lame.exe"
, .

Files are transferred like this:
"lame -f file.mp3 file_resample.mp3"

Google tormented all day. In some forums, a similar problem popped up, about the operators lfnfor, choise, and there is no solution anywhere.
')
It is known that lfnfor is an undocumented feature, maybe in SP3 it stopped working altogether?

Only hope remains for you.
Thank.