Hi, I received a mobile iPhone 5 last Fri from carphone warehouse along with a sim card with tmobile on a 24 month contract. I switched phone on and it kept coming up invalid sim and that was it so yesterday they swapped my iphone over for another new one. Thought great and was really happy. set it all up only to find I can make calls but cannot send or receive any text msgs at all.

I went to register my details on the tmobile site and it keeps coming up invalid sim. I rang tmobile up and they are saying its not registered with tmobile my details and that I would have to get another sim card as that is an old one and is expired.

My question is if it was expired how can I make phone calls and what do I do next..