firmware unavailble for wndr3400v3

> re wndr3400v3 firmware upgrade. [...]

   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.  (In the User Manual, look for "firmware", and,
especially, for a topic like "Manually Upload Firmware to the Router".)
When that fails because of a deficient User Manual, try:

      https://kb.netgear.com/23960

> [...] I followed the instructions [...]

   _Which_ "the instructions"?

> [...] the response is that there is NO firmware available.

   Trust no one, I always say.