iPhone Won't Update
The Problem: Your iPhone won’t update to the newest version of iOS.
The Fix: Connect your phone to a PC or Mac and conduct a force restart as we mentioned above, this will put your iPhone into recovery mode.
You should then see an option to update it, tap to update the phone and once the update has completed, your phone should be working again.
If the update option doesn’t appear, you’ll have to restore your phone. This will remove all the data from your iPhone and restore it to its factory settings.
You will, however, get the latest software version and you’ll be able to restore your phone with backed-up content.