Redirect adds index.php to the url and redirects to wrong controller / action

Hi,

I have the following redirect: $this->response->redirect('unit/index'); this redirects to https://dev.example/index.phpunit/index when changing the redirect to: $this->response->redirect('/unit/index'); the page goes to: https://dev.example/index.php/unit/index basically the redirect is adding index.php (which loads the default IndexController) into the url can anyone advise why this happening? I am using nginx and my host config file is as follows:

server {
    # Port 80 will require Nginx to be started with root permissions
    # Depending on how you install Nginx to use port 80 you will need
    # to start the server with `sudo` ports about 1000 do not require
    # root privileges
    # listen      80;

    listen        80;
    server_name   dev.example;

    ##########################
    # In production require SSL
    # listen 443 ssl default_server;

    # ssl on;
    # ssl_session_timeout  5m;
    # ssl_protocols  SSLv2 SSLv3 TLSv1;
    # ssl_ciphers  ALL:!ADH:!EXPORT56:RC4+RSA:+HIGH:+MEDIUM:+LOW:+SSLv2:+EXP;
    # ssl_prefer_server_ciphers   on;

    # These locations depend on where you store your certs
    # ssl_certificate        /var/nginx/certs/default.cert;
    # ssl_certificate_key    /var/nginx/certs/default.key;
    ##########################

    # This is the folder that index.php is in
    root /Sites/example/public;
    index index.php index.html index.htm;

  charset utf-8;
    client_max_body_size 100M;
    fastcgi_read_timeout 1800;

    # Represents the root of the domain
    # https://localhost:8000/[index.php]
    location / {
        # Matches URLS `$_GET['_url']`
        try_files $uri $uri/ /index.php?_url=$uri&$args;
    }

    # When the HTTP request does not match the above
    # and the file ends in .php
    location ~ [^/]\.php(/|$) {
        # try_files $uri =404;

        # Ubuntu and PHP7.0-fpm in socket mode
        # This path is dependent on the version of PHP install
        # fastcgi_pass  unix:/var/run/php/php7.0-fpm.sock;

        # Alternatively you use PHP-FPM in TCP mode (Required on Windows)
        # You will need to configure FPM to listen on a standard port
        # https://www.nginx.com/resources/wiki/start/topics/examples/phpfastcgi$
        fastcgi_pass  127.0.0.1:9000;

        fastcgi_index /index.php;

        include fastcgi_params;
        fastcgi_split_path_info ^(.+?\.php)(/.*)$;
        if (!-f $document_root$fastcgi_script_name) {
            return 404;
        }

        fastcgi_param PATH_INFO       $fastcgi_path_info;
        # fastcgi_param PATH_TRANSLATED $document_root$fastcgi_path_info;
        # and set php.ini cgi.fix_pathinfo=0

        fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
    }

    location ~ /\.ht {
        deny all;
    }

    location ~* \.(js|css|png|jpg|jpeg|gif|ico)$ {
        expires       max;
        log_not_found off;
        access_log    off;
    }
}

Thanks