Cisco 7841 Replace an existing phone. Asking for Primary extension/PIN

[Will Pettit]

Hi, 

We have a few new (probably refurbished) 7841's that when you boot them up, ask for a Primary Extension and PIN as part of migrating a phone. 

We have never set up the phone migration settings. The phone is configured in CUCM.

I've tried resetting the settings, but it doesn't work.

Is there a quick fix for this?

Thanks