need help to update firmware LG G2
 

i tried to update LG G2 D800 , but colud not update ,
please Octopus Help me to upgrade firmware since installed firmweare is too old .
thakns
Installed Version 4.4.2
upgrade version :- LGD800AT-01-V20c-310-410-FEB-02-2014+0 <--- Downloaded from support Area

Unfortunately, for this phone model D800 new firmwares aren't available at the Support Area, we will try to find and upload to the Support Area, if You can get the firmware for this phone, You can convert firmware via Octoplus LG Tool( Firwmare convertor button in Software) into *.oct file format that You can reflash the phone.

can you advice me what upgrade version is compatible with it ?
this file downloaded from internet , LGD800AT-01-V10d-310-410-AUG-14-2013
i want to upgrade On Kitkat
thanks