Please help, my Nighthawk x6 r8000 randomly drops internet connection

> [...] since last firmware update [...]

   To me, that sounds like a clue.  "Newer" and "better" are spelled
differently for a reason.  I'd try loading the previously working
firmware.

   Visit http://netgear.com/support , put in your model number, and look
for Downloads.  (For older versions, under Firmware and Software
Downloads, look for "View Previous Versions".)  Find the kit(s).
Download the kit(s) you want.  Read the "Release Notes" file for
instructions.

   Recently, Netgear has stopped including actual instructions in its
firmware "Release Notes" files, so all you may see there is a hint like:

      To update your router's firmware, follow the instructions in your
      router's user manual.

   In that case, visit http://netgear.com/support , put in your model
number, and look for Documentation.  Get the User Manual.  Look for
"firmware" and/or "update" for the details.