[MENTION=38055]Yasir Nadeem[/MENTION] [MENTION=123761]winchester khan[/MENTION]
That was on a Nexus 5. Unlocking Bands on Nexus 5 has been verified. [MENTION=173]venom[/MENTION] has a LG G2. Even though both of them have the same SoC, I can't find a single post on XDA which talks about unlocking Bands on the G2.
So [MENTION=173]venom[/MENTION], I'd suggest you don't take any risk which might end up bricking your phone. Especially if you don't have much experience with rooting and flashing ROMs etc.
[MENTION=123761]winchester khan[/MENTION], if you know someone who's unlocked band 3 on a G2, or if you know of a verified tutorial which shows this, please share it.