iPhone 4S stuck in activation loop

My iPhone 4S began asking me to complete activation last Thursday. I was unable to complete the activation it came back with message that it couldn't complete because server was not responding. I tried to use iTunes but that didn't work either. Now it's not working at all but will only show the iTunes screen. From several contacts with Apple and Sprint it looks like there was some kind of software pushed on my phone but no one wants to take responsiblity. It cannot be updated or restored or even erased and restored from a backup.