I get one notification twice on instagram and whatsap

Hello Popup70,

Let's use the steps below to make sure that your iPhone is up to date: Update your iPhone or iPad - Apple Support

1. Back up your device using iCloud or your computer.

2. Plug your device into power and connect to the internet with Wi-Fi.

3. Go to Settings > General, then tap Software Update.

4. If you see more than one software update option available, choose the one that you want to install.

5. Tap Install Now. If you see Download and Install instead, tap it to download the update, enter your passcode, then tap Install Now. If you don't know your passcode, learn what to do.

You'll also want to make sure that those apps are up to date: How to manually update apps on your Apple device - Apple Support

Should you continue to receive duplicate notifications from those particular apps, you'll want to reach out to the developers: How to contact an app developer - Apple Support They'll be in the best position to help further with notifications from their app.

Take care.