Just in case someone is as lost as I was for hours, here is a tip.
I wanted to make a custom sound for my alarm clock, and kept thinking I'd put the mp3 in my notifications folder. This to no avail.
I finally caught the word "ringtone" on the page to set up the alarm.
After placing the mp3 in the ringtone folder, it worked.
Good luck to you all.
Glad to hear that you got this sorted, and thanks for sharing the great tip with the Community, Mark! 🙂