GT-N7100 unknown baseband imei null/null

when i received this cell lolly pop running inside it with custom recovery. and customer says that after upgrade baseband gone and imei null/null.
even cant go to recovery only running lollypop.
i flash it with pak reagon official firmware and with pit. it's internal memory is 16GB.
after flash i read csc in recovery mode and it shows "CHN"
after that i do factory reset it and restart. rom was not entering in manu and showed
firmware upgrade encounter an issue. please select recovery mode.............................................. .........

then i use cf auto root for this and after this 4.4.2 running well and unknown baseband and imei null/null
i also write efs download from here
http://www.gsmindia.in/forum/samsung...re-tested.html
but nothong happen.
i also downloaded CHN reagon firmware but when i try to flash it is showing sboot.img sending fail and stop flashing.

any solution please?....................................so confused