1. From the Home screen, tap the App Store icon.
2. Tap the Updates symbol in the App Store's bottom right corner.
3. To update the app, tap the Update option next to Instagram.
4. If multiple app updates are available, press on Update apps individually or select Update All apps at once if multiple app updates are available.
After you've updated your applications, reboot your iPhone SE. then try to launch Instagram to see how it works after installing the update.