Nginx 404 in /admin site

[jurek1337]

hi
i downloaded newest version 1.7.46 of grav + grav admin plugin
installed on turnkey debian 12

and when i am going to /index.php site i was redirected to /admin and i see 404 not found error
while i try other subfolders like /logs, /images, i see 403 forbidden
so imo nginx is configured properly
i also changed of course in nginx.conf the root of grav to /var/www, changed permissions, owner, and group-owner, updating the admin plugin

I will be grateful for your help