Android provides features for notification with default sound. If you get any notification it’s give a sound for get notification for example mail notifications, text message, social media, alerts etc. It’s also provides us when device is lock screen mode. It can be a handy way to help you see whether a notification is important or not without actually unlocking your phone. However, it also means that anyone that picks up your phone can see snippets of information that might be private.

Android offers to hide notifications alert beep sound. If you want to hide notification alert sound then follow below steps-:

1.      Open Settings.

2.      Click on Sound & notification.

3.      Now scroll down the content and click on when device is locked or While locked. 

4.      Choose Hide sensitivity notification content.

The "Show all content" option means you'll get notifications on the lock screen and Samsung won't attempt to hide any information it thinks might count as 'sensitive'.