Sign out of the app...
And try to sign in again....
I expect you can't sign back in...
The Live ID and Sky ID are linked online when the pairing breaks on Live server side you lose access...
Sky news is free to every one with the app as the stream is not DRM'ed...
With out the pairing working the app is unable to find your Sky go extra details and sub details as the account is not linked and gets rejected...