How to get rid of Wi-Fi problem in LG G2 smartphone?

Are you stuck with wi-fi problem in your LG G2 model of smartphone? Our technical experts are here to help you sort it out.

My brother has an LG G2 smartphone. He has been using the phone since its launching time. He is now facing Wi-Fi problem in it. He has also updated the software version and the latest possible version of OS to LG G2 but the problem remains the same. He also opened the device and has put a packing in it as per the advice of Video from YouTube. Still, he is facing a problem. Can you help in this matter?