Installing the latest iOS version will likely solve the problem if it's caused by system issues in the older iOS version.
Update your iPhone to the latest iOS version available:.After deleting, go back to the App Store to download and reinstall Avast Security & Privacy on your iPhone. Uninstalling Avast Security & Privacy from your iPhone will clear cache and data from the application, delete any temporary files and data that might have been corrupted and caused the Avast Security & Privacy app to crash or not work. Uninstall and reinstall Avast Security & Privacy iPhone app:.If an update is available, an "Update" option displays.Goto the AppStore on your iPhone screen.Update Avast Security & Privacy app to the Latest Version for iOS:.Restart your iPhone to apply the recent changes and refresh the system.
Close the rest of your background apps is the same way. Swipe the Avast Security & Privacy app up to close it.Locate the Avast Security & Privacy app.Swipe up from the bottom to the middle of your screen until the App Switcher opens.
Here's how to quit and restart the Avast Security & Privacy app on your iPhone: Restarting the Avast Security & Privacy app helps clear any minor glitches from the app's cache.