I can't create teaching materials. Is it copyright?

There was a Youtube video of an American podcast that I wanted to use as a new teaching material which have two and a half hours, so I converted the video to mp3 and created the teaching material by dividing the audio into four every 45 minutes, but from the third one I can’t import it successfully.
What factors can be considered?

  • “Succsessfly import” will be displayed, but if you click “View lesson” after that, the previously created teaching materials will be displayed.

That sounds like a bug. Did the lesson appeared after all? If not, can you please send us a link to that course to support(at)lingq.com? Thanks!