Server Time out Apache2 Varnish Ubuntu 16.04 - apache

Question

I have a server configured on Ubuntu OS with varnish on port 80 -> apache2 on port 8080. if I go to a folder without a trailing slash ( http://www.example.com/test ) it shows:
This site can’t be reached
www.example.com took too long to respond.
But if it works perfectly with trailing slash. (http://www.example.com/test/)
My .htaccess is:
RewriteEngine On
RewriteCond %{HTTP_HOST} ^[^.]+\.[^.]+$
RewriteRule ^(.*)$ http://www.%{HTTP_HOST}/$1 [L,R=301]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_URI} !(.*)/$
RewriteRule ^(.*)$ /$1/ [L,R=301]
<IfModule mod_expires.c>
ExpiresActive on
ExpiresDefault "access plus 30 seconds"
ExpiresByType text/html "access plus 15 days"
ExpiresByType image/gif "access plus 1 months"
ExpiresByType image/jpg "access plus 1 months"
ExpiresByType image/jpeg "access plus 1 months"
ExpiresByType image/png "access plus 1 months"
ExpiresByType text/js "access plus 1 months"
ExpiresByType text/javascript "access plus 1 months"
</IfModule>
<ifModule mod_headers.c>
Header set Connection keep-alive
</ifModule>
ErrorDocument 404 /404.html
I have changed the ports of all virtual hosts and ports.conf to 8080 and also the port for varnish to 80 on varnish.service file. The root folder have only html contents. And there is a Wordpress installation on (www.example.com/blog).