Well first off, somehow Lawrence above was wrong. When I switched from my iPhone 6 to my iPhone 12 Mini in January, all my custom ringtones came over and they all worked, using the iCloud Backup then Restore to new iPhone process. For some weird reason, back on Mar 7, all the ringtones disappeared from my new iPhone. To fix this, and some other issues, I wound up deleting ALL Music and also Home Videos/Downloaded Videos from my new iPhone (I had a lot of dupes and manually cleaning them up got messy). Then I connected to iTunes and synced and got all those corrected. My phone now had all my MUSIC and my Home Videos/Downloaded Videos, without duplicates. Then I had to fix playlists (I think just recreate one that was missing, others were there). Next, I still could not get this newer version of iTunes to play nice with ringtones, (I initially loaded them onto my old iPhone using a much older version of iTunes (angers the heck out of me that Apple took away functionality in later versions of iTunes). So I wound up installing Copy Trans Manager on my PC and this made adding the ringtones simple, I just clicked and dragged them from my iTunes Folders into this and they went onto my phone. I also found I can use it now to simply add new music or even videos (like mp4 movies to have for a flight/trip).