The following info may help the clever people on here provide help.
When was it last working? Has anything been changed since then? What lights are showing on your SHub? Could be an external fault. Have you checked the service status? Have you tried turning off the SHub and turning back on after a few minutes? Do you use your own router or the SHub?
Sorry to hear about your loss of service, I really hope you're back up and running now. I've tried to confirm this, but I can't find your account info. If you'd like me to investigate further, please drop me a PM with your address.
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