Alternatively, alter the volume via the Control Center by swiping down from the top-right of your screen (iPhone X and later) ...

your volume buttons can control your alarm. Use them to snooze or turn off alarms with a simple press, providing a handy alternative to on-screen controls. In critical situations, your iPhone can ...

Apple removed the volume slider from the iPhone lock screen, and it only appeared when the user used AirPlay. Now, after installing iOS 18.2 beta, users can bring back that capability and control ...