I've been having the same issue with error 0. I've spent 3hours on this nonsense.
I've also have not been able to make and recieve calls today.
I've had people trying to contact me and I never knew til hours later when they contacted my child to get hold of me.
Never got the government 'alert' sound either.
Done an update. Nothing.
Been through all the sky help, reset networks, create new access point and the sky messaging bot.
Tried an old phone and nothing.
This happened in January when I got the handset, just briefly though.
Today has been the worst.
Sky need to do better.
