I was in he process of setting up my new MotoG from a windows phone, and was having problems syncing my contacts through gmail, but that's another question.
I was putting my micro sim back and forth between the two phones and eventually left it in my old phone because I still hadn't managed to get my contacts over. (I did do this quite a few times)
This morning I noticed I had no service from Talktalk.
Tried it in my new phone, but the same there.
Phoned TT and tried to reactivate my sim, but still nothing.