wordpress LEMP stack 404 issue

I have a LEMP stack setup with two single site WordPress installations: site1 and site2.

For some reason, I noticed when I try going to a page that doesn’t exist on site2, I get the 404 page for site1. How do I make the 404 error on site2 display for site2?

im thinking it is my wp directory structure on the server but not sure..

my main site is in var/www/html
for site 2, i have a folder within var/www/html/site2

The page I need help with: [log in to see the link]