Strangely when I login to mobilesecurity there are no devices registered...?
When I login to my Norton Account it says there are no installs left ,even though the expiry still says Apr 25, 2013. Looks like the phone factory reset then reinstall of Norton has killed the license key.
Click the Norton Mobile Security icon. You can see your device listed along with the license info. Click the trash icon next to it to remove the device.
Activate and register NMS from your device using your Norton Account.