Hi,
There are two settings to check / adjust before this works.
1 – Phone settings -> Apps -> Aqua Mail -> Notifications -> enable “Show bagde”.
This however will only trigger on single-message notification, so you’ll have either nothing or a “1” on the badge.
To make it work for multiple-message notifications, please:
2 – Aqua Mail settings -> message notifications -> enable “Smart Watch enhancements”.
This also changes how on-phone notifications look. You’ll be able to expand (swipe down) on a notification that’s “about” more than one message, turning into individual “cards”, one per message, each with its own action buttons (mark read and so on).
This “enhanced” notification style – which first appeared in Android 7.0 – works with the new Samsung badge feature as expected, even when there are multiple unread messages.