Killed App


an unfortunate incident i updated my Nokia 2.2 on 01 May 2020 to Android 10 (Build Number 00WW_2_300_SP02)

Now. all my background app always killed immediately after im leave it off screen.

any solution ?

  1. already hard/master/soft reset.
  2. already install/uninstall whatsapp ( killed app example )
  3. already do developer option stuff.
  4. already uncheck/check batery saver, notification, data saver, permission stuff, and in app settings.