Oneplus has a feature “Zen mode”, which completely locks down the phone to focus. But when this is activated and the alarm goes off, the phone does not show the interface to either stop it or snooze it, so the only way then is to completely shut down the phone to make the alarm stop.
I’m not sure wether or not this is fixable by sleep as android
Hi @Tim_Willems , the alarm screen with the “Draw over other apps” permission granted is eligible to show on top. If the system blocks it, there is sadly no way we could force the system further.
Are there any settings options to configure the behavior of the Zen mode?
Hi,
That is already enabled, I think the OS forces that to be above all the other apps. I’ll go create a ticket with them, but I don’t think they’ll be quite as responsive as you are 
Hi, I did not find much information, but it seems the mode does not allow even the alarm screens.
I was thinking - you could use the Flip to snooze and Volume or camera button effect (for dismiss).
The duration of snooze for flip to snooze feature is controlled by the value in Settings > Alarms > Snooze >Snooze duration (or Snooze duration in per-alarm settings).
This does not solve the issue directly, but it would allow you to control the alarm even without the alarm screen.
Would this help?