How to fix an iPhone 8 Plus that keeps crashing or shuts down unexpectedly after installing an iOS update

There's a potential you'll wind up with a problem if the new iOS update changes your current settings automatically. As a result, some services or iPhone features may stop working or fail to finish their routines due to an error. You may clear this by resetting the settings to their default values and then configuring the relevant options one by one. There will be no data loss as this reset will not impact any data saved on the internal memory. Here's how to do it:

1. From the Home screen, go to Settings.
2. Select General.
3. Reset may be found by scrolling down and tapping it.
4. Choose Reset all settings from the drop-down menu. This will restore the default system settings without damaging your iPhone data.
5. If asked, enter your device's passcode.
6. Then tap the option to confirm settings reset.