Galaxy S7 calendar reminders work irregularly

[Old_Professor]

Yesterday my reminders were working; today they're not. I'm using aCalendar and Calendar Event Reminder. I think I've I've exempted every calendar from power management, but the options I see on my phone are different from those shown in all older posts. I just entered a test appointment on my calendar and a reminder sounded off over and hour late. Of course, the test sounded off on schedule.

Suggestions appreciated.