[Refurbished][D855] Network not came after LP update but sim detecting

My friend has LG G3 D850 but that set has motherboard of D855 32GB 3GB RAM (as far IMEI no check from imei.info), It was on stock 4.4.4 but recently he updated via LG PC suite and after that SIM is reading but network not coming. SIM menu is there. Also getting a warning after every reboot.