Without your valuable response, I can only give you a general answer, but I hope this helps.
Please follow the below steps to resolve the issue.
1.To import the entire song set the current song section to Automatic; otherwise, only the portion of the song that fits the current song section is imported.
2.To get a list of tracks, tap the Tracks View button.
3.Tap the Loop Browser button in the control bar, then tap Music.
4.You can search for songs by name, or browse by album, artist, genre, or playlist.
5.To preview a song, tap it in the list. You can control the preview volume with the slider at the bottom of the list.
6.Drag a song left or right to show Tracks view. Align the left edge of the song with the bar or beat on the ruler where you want it to start playing.