Changing an iPhone's alarm sound and volume can be a bit confusing since it can be done in Apple's Clock app and the Sleep section of the Health app. An unexpectedly loud alarm or annoying ring can be a very startling thing to wake up to, so it's important to fine-tune this setting and start the day off right. The iPhone offers several options from gradual and pleasant to a bit more jangly and persistent, depending on what's needed.
With iOS 15, Apple included a Sleep Focus option that can help
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