I bought a new mobile from an O2 shop three or four weeks ago, but kept my existing pay as you go SIM card and number. Everything was fine until last night, when my phone suddenly displayed 'Unregistered SIM'. The signal bar is full, but I can't connect to any network. I've taken the SIM out and reinserted it several times, cleaned the contacts, etc. Also, I can view the available memory on the SIM, and the contacts stored on it, which suggests that there isn't a problem with the chip or anything. Why is this happening? I've topped up and made outgoing calls in the past 30 days, so it can't have been deactivated. Cheers.
there was an issue with the automated systems last night resulting in them disconnecting pay and go sim cards as they where believed to be out of date. The time scale we have been given is 2-24 hours for those sims to be reconnected.
The same thing has happened to me. It was working fine until last night and i got 'inactive sim' on the screen. I hope they do reconnect it and soon. I hate not being able to use my phone. Also, how do you know this?