1- LG United Mobile Driver Download Here
2- LG Flash Tool 2014 Download Here
How To Flash LG G2 D802 Android 5.1

Open LG Flash Tools 2014 and Select Type ( CDMA ) OR PhoneMode ( CS_Emergency )
Select KDZ File ( LG G2 D802 KDZ Firmware )
Choise Normal Flash Just Update You Device
Choose CSE Flash Otipon will Formate All Your Application Data or Phone Storage
Turn Off You Device and While Pressing both the Volume key Connect Your Device PC Screen Will Show Download Mode icon
Update this Device or wait for Driver installation
Then Select Your Languse Region and Select OK
Wait You are Update Done

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