you may be able to downgrade to iOS 10.3.3 and then re-upgrade. See instructions below.
http://www.macworld.co.uk/how-to/apple/how-downgrade-from-ios-11-3664217/
you may be able to downgrade to iOS 10.3.3 and then re-upgrade. See instructions below.
http://www.macworld.co.uk/how-to/apple/how-downgrade-from-ios-11-3664217/