No longer automatically downloading on Samsung S24

I’ve had K9 Email forever, and it recently stopped downloading automatically behind the scenes.

I am not sure of the timing, but Samsungs did have a major UI update recently.

When I open the K9 app manually, I get a flood of emails. But nothing behind the scenes.

Check K9 settings and also device settings - apps - all apps - K9. Make sure it has unrestricted battery and background use enabled.

Please also check Configure push email for Thunderbird for Android | Thunderbird for Android Help