No sound effect of Bedtime after updating 13.4.1

The sound effect usually goes with Haptic when it reaches the sleep time I set in Bedtime. But recently I find that it does not play that sound and Haptic anymore, it just turns into sleep mode silently(Do not disturb during bedtime, calls will be silenced ..... until your wake up alarm at ...). I need that sound and haptic to notify me of sleep time, how could I bring it back?

P.S. I checked out the settings, there's no notification switch for the alarm app, so the notification of bedtime can't be turned off. And the Do Not Disturb is also off before sleep time.

I would also be greatly appreciated if I can get the original sound effect file of bedtime, because I am recently making a vid about my life with Final Cut Pro, that sound effect is part of it. And that's why I found it missing, when I tried to record that sound it just turned on silently.