No notification on iOS 16.4/iPadOS 16.4

When a notification is sent by my WP website, I receive it without a prob on all my browsers. But nothing on my iPhone and iPad.

My website is added as a web app on my home screen. I received the system message to allow notifications and accepted (it is active, I checked). I then receive without a prob the very first notification I send. But nothing anymore after that.

If I delete the web app from the home screen and reinstall it, again, I receive the very first notification sent, and nothing anymore after that.