Alarm clock going off but not making any sound

Had this problem years ago and here we are again with iOS 26. My alarm clock is going off in the morning without any noise. I woke up a half-hour late today to see my alarm was going off but the phone was completely silent. When I check the volume setting, it has somehow mysteriously set itself to silence. I've not once silenced the alarms. I'm baffled as to why iOS would let any user silence their wake-up alarms. That literally makes no sense.

Any advice on how to fix this would be appreciated. Have already reported the issue to Apple. My phone is up-to-date.