itunes
why didn't all of my songs transfer from my old iphone to my new iphone?
iPhone SE, iOS 12
Question marked as
The only songs that would "transfer" from one iPhone to another are songs that you bought from the iTunes Store or you leased with an Apple Music subscription. For songs that you imported into iTunes from a CD, for example, you would have to sync your new iPhone to your computer.
Redownload apps, music, movies, TV shows, and books - Apple Support
Use iTunes to sync your iPhone, iPad, or iPod with your computer - Apple Support