I accidently set my husbands new iPhone 6 up under my back up. Now, when I receive texts he receives them too. Its making it appear that I have two phones. We share an iCloud account. Can I do a complete "erase all content and settings" to fix his phone? It won't deactivate his phone with Sprint?
If you go to
Settings -> General -> Reset -> Erase All Content and Settings
This will restore the device to an 'Out of the Box' state and allow you to start the process of set up again. It will not deactivate the device as far as the carrier is concerned and you can still make and receive calls and SMS but will lose contacts and call history, etc....