There is already another question like this (Alarm is disabled when device is switched off) but my question is slightly different from those.
In my new phone with Android 7.0 Nougat, I found something strange.
Suppose, I have set an alarm at 7:00 AM and at that time, the phone is switched off. I found that the alarm works absolutely fine - the screen turns on and the ringtone is played.
But, if the screen is not touched within about 15 seconds, such as, snoozing or dismissing the alarm, the screen turns off permanently, means that even if I hold down the power button, it doesn't turns on. But the ringtone continues to play.
Then I need to pull out the battery, reinsert it and again restart the phone.
Now I have somehow coped up with this issue by setting the Automatic power on time to two minutes before the alarm, that is, at 6:58 AM. But, that is not the solution, because I may sometimes set the alarm to before the power on time and I may forget to change the power on time. I am really fed up with this problem.
Why does this happens and how can I solve this issue?