Hello,

I'm having a big problem with my phone at the moment.

I tried to flash custom ROM, but something somewhere went terribly wrong.

I did read some guides on flashing before attempting this and did make some precutions as well.
Such as creating ROM backup with CWM and copying efs folder with Root browser.

Unfortunately I didn't succeed with the flash. Now the phone can turn on, but there is no network service, and IMEI number is missing.
I tried to go back to my backed up ROM, but that didn't fix the problem.

I also noticed that on the back cover of the phone I have T-Mobile written on, but the phone itself has AT&T branding, such as AT&T boot logo and some AT&T apps. In most places the model number is SGH-I747 which is AT&T variant of the phone indeed.

But When I entered download mode via volume down + home button + power button, the model number presented there was T999 which is model code for T-mobile version of the phone.

Is there something that can be done at this point?