I had the same issue, it was due to restore settings from google backup, i had to clean flash and when i had the option to restore google account disabled only the option restore settings, i only restored apps, sms....
Have you clean flashed recently and restored Google backup?
I had a similar problem but with clock alarms not wake lock screen, it was due to google settings restore.
i had to restore apps, sms, but not settings.
Please can someone test alarm on DND and tell me if is ok or has the same issue as me?
I'm thinking that could be the my Micloud Backup that can be the cause.
I didn't want to clean flash again without know if is a bug or not.
My alarm clock ring at the right time but isn't popup and i had to unlock my Mi 8 to go to notifications and turn off the alarm, is happening only in DND mode, in normal mode is OK, can some one help me?
Goolge clock work as it should but i want to use the Miui clock.
Today my alarm clock ring at the right time but isn't show anywhere i had to reboot my Mi 8 to turn off the alarm, can some one help me? what can i do to solve this?