Q: No notification sound from Whats app

Hello there, Nana.

It seems like you're having issues with not hearing notification sounds form the WhatsApp application on your iPhone 6. The following Knowledge Base article offers some great insight into Notifications and some recommendations if you're not receiving them:

Use Notifications on your iPhone, iPad, and iPod touch

Types of notifications

Notifications from apps on your iOS device can have these styles:

• Sounds/Vibrate: A sound alert plays.
• Banners: A banner appears on the screen.
• Badges: An image or number appears on the app icon.

Your iOS device can also use your location to send you relevant alerts based on where you are. For example, you might get a reminder to call someone when you get to a specific place or when you leave for your next location.

If you don't want these types of alerts, you can turn them off. Go to Settings > Privacy > Location Services > System Services and tap the alerts and services you want to turn off. Learn more about Location Services.

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If you don't see notifications for a specific app

To get notifications, you need to be connected to a Wi-Fi or cellular network. If you’re not getting notifications for a specific app, try these steps:

1. Make sure that the app supports notifications. Go to Settings > Notifications, select the app, and make sure that Notifications are turned on.
2. Make sure that you’re signed in to your Apple ID on your iOS device. Go to Settings > iTunes & App Stores and enter your Apple ID and password.
3. Make sure that Do Not Disturb is turned off. Go to Settings > Do Not Disturb and tap Manual if it's turned on.
4. If you’ve recently installed an app or restored from a backup, open the app to start getting notifications.

Additionally you can look to this article for help with troubleshooting an app that is not performing  as expected:

If an app you installed unexpectedly quits, stops responding, or won’t open

Restart the app

Close the app and open it again.

Restart your device

Turn your device off and back on.

Check for iOS and app updates

1. Make sure that you're using latest version of iOS.
2. Open the App Store and tap Updates.
3. If updates are available, tap Update All.
4. If asked, enter your Apple ID password.

You might need a Wi-Fi connection to update some apps.

Install another app from the App Store

Try installing a different app that you don't have on your device. Find a free app from the App Store, and remember to use the same Apple ID that you used to download the app that you're having issues with.

Delete and reinstall the app

1. Tap and hold the app until it jiggles.
2. Tap the on the app.
   
3. Press the Home button.
4. Go to the App Store and download the app again.
5. Wait for the app to download, then open it from the Home screen.

Contact the app developer

If you see this issue again, contact the app developer for help:

1. Find the app in the App Store.
2. Tap the app, then tap Reviews.
3. Underneath App Store Customer Reviews, tap App Support.
   

Thanks for reaching out to Apple Support Communities.

Cheers.