I have had this issue for the last few months where my device enters a "deep sleep" mode on occasion when left idling for any time longer than an hour. The device will not send any notifications until I unlock the device and then I will be bombarded by all of the notifications in that time at once. Any help would be greatly appreciated.
Things I've tried:
- Making sure google play services battery mode is set to unrestricted.
- Resetting app permissions to defaults and granting permissions to apps upon reopening.
Here is a screenshot of what the battery usage page shows. The gap area is the time where my device is in this "deep sleep" mode.