Question about how my music sorts

I have all my music on my Mac and my iPhone.

On my Mac it's all in the Apple Music App, and all the songs are sorted by artist, Last Name first.

I set the sort order by pressing Command-I, then clicking the Sorting tab.

OK.

BUT- occasionally, I have music files that I've sorted (on my Mac), by Last Name, First Name, BUT on my phone, they show up sorted by First Name, Last Name. I check the individual music files, and they're set to sort Last Name first, (in fact on my Mac, they ARE sorted Last Name first), but they still show up First Name first on my phone.

Any ideas?