Alarm won’t play music

My new iPhone C S Max alarm will not play music but plays only horrible default tones. I called Apple they had me reset the phone which was a hassle. It did nothing. I went to the Apple Store and they wanted to wipe The phone to factory settings and restore from the same material that was brought over from my old iPhone 6 on September 12 - 2018 a month ago! I declined I didn’t see the point . It would be the same thing that was put on the phone a month ago . I tried everything in the Apple thread that others had written about since 2015 or before.

Restarted

raised volume

tried both purchased songs and songs from my personal library

erased all alarms tried new songs

Nothing worked. At the Apple Store they say it’s not my phone it’s the software. I fail to understand how we could have this problem and nobody has an answer ! Help!! It it isn’t isn’t resolved in the next 48 hours I’m returning this phone regardless of whether not it’s a hardware or software issue. I’m over it ! I’ll buy an eight and see if I do better with that .