Music purchased on iTunes that is now in Apple Music - access from Mac okay but no access with iPhone

I have a whole library of music and playlists on my MacBook that were downloaded from iTunes over the years. I can access them on my computer though Apple Music. They all used to be accessible on my iPhone as well, but when I recently updated my iPhone, I now have no access. My Apple Music library on the phone is completely empty. I am logged in with the same iCloud account on both my MacBook and my iPhone. Does anyone know how to remedy this situation?