Unable to Activate an Update is Required iPhone 6 Plus

I recently had a Network Error signal on the top of my iPhone, and was unable to send text messages or call, and receive any.

I tried to update and restore the software on my iPhone and now I cannot activate the phone to setup again after restoring to factory settings, as the new error is "Unable to Activate, an Update is Required"

Just wondering if there's anything I can do at home before I have no choice but to take it in to an Apple Repairer?

Cheers :)