1。 Tap Change to open the built-in clock application and alarm interface of iPhone, and select the change option without alarm clock. 2。 Click the open interface to display sleep off, select the yellow open icon and click Open. 3。 Drag the adjuster to jump to the interface of changing the wake-up time, and the interface drags the adjuster to adjust the bedtime and wake-up time (see Adding or Changing Sleep Timing in Health on iPhone). Turn off the next wake-up alarm. You can turn off the next wake-up alarm clock during sleep, or turn off all wake-up alarms during sleep. Tap Alarm Clock, then tap Change.