Nginx Rewrite WHMCS on SubFolder

im running WHMCS on subfolder

mydomain.com/support

# Knowledgebase
RewriteRule ^knowledgebase/([0-9]+)/[a-z0-9_-]+\.html$ ./knowledgebase.php?action=displayarticle&id=$1 [L,NC]
RewriteRule ^knowledgebase/([0-9]+)/([^/]*)$ ./knowledgebase.php?action=displaycat&catid=$1 [L,NC]
RewriteRule ^knowledgebase$ ./knowledgebase.php [L,NC]

im using online converter, and got this rewrite

rewrite ^/knowledgebase/([0-9]+)/[a-z0-9_-]+.html$ /./knowledgebase.php?action=displayarticle&id=$1 last;
rewrite ^/knowledgebase/([0-9]+)/([^/]*)$ /./knowledgebase.php?action=displaycat&catid=$1 last;
rewrite ^/knowledgebase$ /./knowledgebase.php last;

nothing happen, then change ^/knowledgebase/ to ^/support/knowledgebase/

but when try access knowledgebase with SEO Friendly URL

403 Forbidden

nginx

Please help me

you don't have to change these rules (add subfolder name) as .htaccess file should be located inside /support/ already!

what do you need to do?