Samsung Galaxy S4 AT&T i337 New Security Easy Unlock 16.5

First Root Your Mobile With V-Root 1.7.2
Then
*#0808# dm+modem+adb Press ok *#9090# choice DM over UART .
connect usb cable and choose Samsung mobile usb serial port
Click on Repair And Tick Repair Efs\Baseband
Tick imei & Fill Your Samsung Original imei
Press Ok
100% Success
mobile is unlock