Why did the alarm clock suddenly stop ringing when Apple's mobile phone was silent?

When Apple's mobile phone is turned on in mute mode, the alarm will still ring, which will not cause the alarm not to ring because of mute. Mute will only make the phone call and text message not ring.

1. First, turn on the mute button on the side of Apple 11 mobile phone and ios13.2.

2. Then click the clock on the Apple phone.

3. after entering the clock interface, click the alarm clock option at the bottom, and then click the+icon in the upper right corner.

4. In the open interface for adding alarm clock, set the alarm clock time and click Save.

5. After the newly added alarm clock is finally stored, the alarm clock will still ring when the mute button is turned on.