My IPhone 3GS says "No Service"
Yesterday I tried to update my IPhone 3GS through ITunes and this caused my IPhone to get stuck in Recovery Mode. I'd Jailbroken this phone earlier in the year so I could use an old SIM card. I've now learned that if you update through ITunes after this it will cause the jailbreak to be cancelled. In any case, I then tried to restore the phone through ITunes and put it back to the original settings. This worked but then the IPhone wouldn't accept either the original SIM card it or the one I'd added after jailbreaking it. Somehow Itunes was able to get the phone back to its status before all of this started and now it is accepting my old SIM card and password. All my old messages and text that was stored before this are present. However, the main display is showing "No Service" so I can't make calls and Safari isn't working (although a Wi-Fi signal is being received). I'm not really sure where to start fixing this? I'd be grateful for any suggestions.