Make sure you “Allow Notification” from your iOS setting.
Revadak from other thread said “I removed the app from the phone and re-installed it.
During initialization it asks to allow push notifications. During the first time installation I didn’t allow this. No idea how to undo that, but at least the re-install->allowing it worked.”
Have you tried restarting the iPhone?
With mine, notifications all of a sudden stop working, but start working again after an IPhone restart…
so far I haven’t figured out why
Do you see the sensors from the mobile app in Home Assistant? Sometimes it also helps removing the mobile app integration and deleting the app on the phone and start from scratch.