[IOS] How can I update app badge when app is in background and GroupChannelPushTriggerOption.off?

I want to update IOS app count badge when my app is in background (or terminated) and user turned off notification of some group channels.
Currently I am setting user’s GroupChannelPushTriggerOption as off when user want to turn off some chatting rooms, but by this setting, my IOS can not update app unread chat count badge when app is in background.
How can I achieve my goal?
Actually, I’m updating badge using Flutter_app_badger when app is in foreground.
Please help me.

Hi, please share all of your relevant code for how you are configuring push notifications.