We're glad you reached out here with your concern. We would like to inform you that third party application stopping miss call alerts on lock screen. So kindly once check your device in safe mode. Placing your device in safe mode disables all third party apps upon startup, to help determine if the use of a third party app is interfering with your device .restart your phone in safe mode. While your phone is powered off, press the power button to turn on the phone, once you see the Samsung logo appear press the volume down key and hold it until you have completely booted up. You will see the words "Safe Mode" displayed in the corner of your screen if done correctly.
