Why doesn't the Apple Disturb mode alarm clock go off?

Do not disturb mode is turned on, and the alarm clock is set incorrectly.

1. Do not disturb mode on: When do not disturb mode is on, the system will block the interference such as incoming calls, short messages and notifications, including the sound of alarm clock. If the Do Not Disturb mode is turned on, the alarm clock will not sound, so you can manually turn off the Do Not Disturb mode to ensure that the alarm clock works normally.

2. The alarm clock is set incorrectly: sometimes the alarm clock is set incorrectly or turned off. Please make sure that the alarm clock is set correctly and the alarm clock function is turned on. In addition, check whether the phone is in silent mode. In silent mode, the alarm clock sound will also be blocked.