xperia c cannot find At&T network

[rk_2014]

Hi,

I came to USA and would like to use AT&T services here. But when I put sim inside it cannot find At&T network. It can show me only T Mobile.

I think band in which AT&T works this phone supports too.

Kindly help

[Shivdutt]

See if your device is unlocked for using foreign careers. There are various steps over the internet to unlock. Trustworthy steps can be found on www.xda-developers.com.

[GowthamSubraman]

Even I have the same problem. What am I suppossed to do? The phones which are cheaper than this pickup networks. Why dont these expensive phones kickup the network? Hope someone would help me with this!!!

[Chispo]

I have the exact same problem.

But at first my 3 or 4 visits to the US it worked fine. Then suddenly im  not able since a year ago. I thought it was something at AT&T level. I went to custome services. They tried many things but nothing, even replacing the sim card. so it is something at the phone level.

Sony please help!