I'm terribly sorry to hear you had no phone service for 2 days at the time of writing the post. I assure you we don't "shut things down" for the sake of it and I'm hoping there is a quick fix available for you.
I've managed to locate your postcode to check the local masts. These are all showing operation and I can't see there has been any faults in the area either.
If you've been unable to use the SIM card in another handset then it's possible this is the problem or there is a local signal issue that's not showing up this end.
As Lee_B mentioned, the way to get this looked in to is by calling 789 from a Virgin Mobile or 0345 6000 789 from any other phone.
I hope you were able to get this rectified. Please let me know how it all went.