I used to use android calendar provider of os but now i use my custom calendar and i cloned os code for android calendar provider in my app to customize it. i have 2 app and they work with them with this provider and alarm manager send broad cast for reminder from app that has calendar provider but when i used it reminder not set in another app before this it worked with android calendar provider The only thing that made a difference is i moved os provider in my app to customize it
the interesting point is that when i twice close and open app that has calendar provider and databases is set reminder and show notification i develop davx5 app and one calendar app whats that problem?
i tried in some api level but not work at all in android 12 close and open app also not effect in set reminder