iTunes error -50 and 8268 while downloading from iTunes Match

This question has been asked one year ago but not resolved and closed.

I have the same problem, iTunes Match won't download on my new 2019 Catalina Mac some songs that have been uploaded through an old Mac, though they are yet available from ITM on my iPhone and iPad.

I see no obvious reason why, as some songs in the same album, whose songs have all been uploaded to ITM at the same time, are available.