Permanent Alarm
I have an alarm that goes of at 5:26 every morning, but it was not listed as an alarm in my clock app. I deleted all my alarms, and this alarm still goes off every morning and I can’t figure out how to delete it.
Have you accidentally enabled bedtime alarms?. See this:-> Use Bedtime to track your sleep on your iPhone - Apple Support
If yes, turn it off, then restart your device.
Regards
Giulio