If you want to reuse the same music multiple times in your video, you can easily duplicate it directly from the timeline.
To do this, once the music has been added to your project:
In the timeline, select the music you want to duplicate, click on the "..." and then click on Duplicate.
The duplicated music appears next to the original. You can then move it wherever you want in your timeline.
Note: After duplicating a music, you can still extend or shorten the audio block to define exactly the portion of the track you want to use.
You can duplicate a music as many times as needed in your project.