[Q] no service message operator after jelly bean

Hello,

Last night I used the guide provided by CNET UK to root and then flash my s3 with jelly bean it is all fine and the phone makes calls browses the internet and seems stable apartment from chrome crashing every 10 minutes but I have a no service message displayed on the drag down screen. I am on tmobile UK and recently before the upgrade it was showing ee. A colleague of mine has had his phone upgraded with an ota update somehow (the reason I flashed my phone was because mine wasn't suggesting an update was available and I'm impatient) is there a way to get the operator to be displayed?

Thanks

Grant