Exported MP3 file won't play in Music

I haven’t had this problem until today.

I import an MP4 file into Audacity.
I deleted the opening and the dead space at the end.
Everything plays fine and I export it as an MP3 file.
Quicktime plays the new file.

However when I import it into Apple Music, I see the file and if I Get Info, it has the correct length. However it will not play when I press the Play button. And maybe this is significant, but it won’t open in VLC either.

I’m a Windows user so I probably can’t help but, have you tried a different format? Do you need MP3?

If you can stick-with MP4 (AAC), it’s much less prone to accumulated damage from multiple generations of re-compression.