Hi Vikror, I would suggest you to check on your wifi card that was installed inside your mainboard.
Sometimes due to impact, the wifi pigtail cable which is connected to the antenna might come out.
Check if it is properly connected to it.
If it is connected well, consider updating the wifi card driver to the latest version first.
If it does not work and you have a spare card, install it to try, while observing the results.
If the replacement card is still having issues, you might have an issues with the laptop internal antenna.