It’s possible that you accidentally activated the Notification Cleaner feature in dfndr security which turned off your notification alerts.
To disable this feature and receive all notifications again, please follow these steps:
- Open the dfndr security app and tap on Tools
- Scroll down to Clear Notifications and select it
- Tap on the Settings icon in the top right corner of the Notification Cleaner page
- Toggle the switch at the top of the Settings screen to disabled
Notification cleaner has now been disabled and you will receive notifications for all apps on your device again.