Site with subdomains in redirect loop - Nginx configuration Issues

this is the website (the website also have subdomains)

nginx configuration:

# You should look at the following URL's in order to grasp a solid understanding
# of Nginx configuration files in order to fully unleash the power of Nginx.
# https://www.nginx.com/resources/wiki/start/
# https://www.nginx.com/resources/wiki/start/topics/tutorials/config_pitfalls/
# https://wiki.debian.org/Nginx/DirectoryStructure
#
# In most cases, administrators will remove this file from sites-enabled/ and
# leave it as reference inside of sites-available where it will continue to be
# updated by the nginx packaging team.
#
# This file will automatically load configuration files provided by other
# applications, such as Drupal or Wordpress. These applications will be made
# available underneath a path with that package name, such as /drupal8.
#
# Please see /usr/share/doc/nginx-doc/examples/ for more detailed examples.
##

# Default server configuration
#
server {
        listen 80 default_server;
        listen [::]:80 default_server;
        # SSL configuration
        #
        # listen 443 ssl default_server;
        # listen [::]:443 ssl default_server;
        #
        # Note: You should disable gzip for SSL traffic.
        # See: https://bugs.debian.org/773332
        #       
        # Read up on ssl_ciphers to ensure a secure configuration.
        # See: https://bugs.debian.org/765782
        #       
        # Self signed certs generated by the ssl-cert package
        # Don't use them in a production server!
        #
        # include snippets/snakeoil.conf;

        root /var/www/html;

        # Add index.php to the list if you are using PHP
        index index.php index.html index.htm index.nginx-debian.html;

        server_name _;

        location / {
                # as directory, then fall back to displaying a 404.
                try_files $uri $uri/ /index.php;
        }

error_page 404 /404.html;
  error_page 500 502 503 504 /50x.html;

  location = /50x.html {
    root /usr/share/nginx/html;
  }

set $skip_cache 0;

# POST requests and urls with a query string should always go to PHP
if ($request_method = POST) {
    set $skip_cache 1;
}
if ($query_string != "") {
    set $skip_cache 1;
}

# Don't cache uris containing the following segments
if ($request_uri ~* "/wp-admin/|/xmlrpc.php|wp-.*.php|^/feed/*|/tag/.*/feed/*|index.php|/.*sitemap.*\.(xml|xsl)") {
    set $skip_cache 1;
}

# Don't use the cache for logged in users or recent commenters
if ($http_cookie ~* "comment_author|wordpress_[a-f0-9]+|wp-postpass|wordpress_no_cache|wordpress_logged_in") {
    set $skip_cache 1;
}

  location ~ \.php$ {
    fastcgi_pass unix:/run/php/php8.1-fpm.sock;
    fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
    include fastcgi_params;
    include snippets/fastcgi-php.conf;

fastcgi_cache phpcache;
fastcgi_cache_valid 200 301 302 60m;
fastcgi_cache_use_stale error timeout updating invalid_header http_500 http_503;
fastcgi_cache_min_uses 1;
fastcgi_cache_lock on;
add_header X-FastCGI-Cache $upstream_cache_status;
  }



  location ~ /\.ht {
    deny all;
  }

        # pass PHP scripts to FastCGI server
        #
        #location ~ \.php$ {
        #       include snippets/fastcgi-php.conf;
        #
        #       # With php-fpm (or other unix sockets):
        #       fastcgi_pass unix:/run/php/php7.4-fpm.sock;
        #       # With php-cgi (or other tcp sockets):
        #       fastcgi_pass 127.0.0.1:9000;
        #}

        # deny access to .htaccess files, if Apache's document root
        # concurs with nginx's one
        #
        #location ~ /\.ht {
        #       deny all;
        #}
}


# Virtual Host configuration for example.com
#
# You can move that to a different file under sites-available/ and symlink that
# to sites-enabled/ to enable it.
#
#server {
#       listen 80;
#       listen [::]:80;
#
#       server_name example.com;
#
#       root /var/www/example.com;
#       index index.html;
#
#       location / {
#               try_files $uri $uri/ =404;
#       }
#}

server {
        # SSL configuration
        #
        # listen 443 ssl default_server;
        # listen [::]:443 ssl default_server;
        #
        # Note: You should disable gzip for SSL traffic.
        # See: https://bugs.debian.org/773332
        #
        # Read up on ssl_ciphers to ensure a secure configuration.
        # See: https://bugs.debian.org/765782
        #
        # Self signed certs generated by the ssl-cert package
        # Don't use them in a production server!
        #
        # include snippets/snakeoil.conf;

        root /var/www/html;

        # Add index.php to the list if you are using PHP
        index index.php index.html index.htm index.nginx-debian.html;
    server_name example.com www.example.com; # managed by Certbot


        location / {
                # as directory, then fall back to displaying a 404.
                try_files $uri $uri/ /index.php;
        }

error_page 404 /404.html;
  error_page 500 502 503 504 /50x.html;

  location = /50x.html {
    root /usr/share/nginx/html;
  }

set $skip_cache 0;

# POST requests and urls with a query string should always go to PHP
if ($request_method = POST) {
    set $skip_cache 1;
}
if ($query_string != "") {
    set $skip_cache 1;
}

# Don't cache uris containing the following segments
if ($request_uri ~* "/wp-admin/|/xmlrpc.php|wp-.*.php|^/feed/*|/tag/.*/feed/*|index.php|/.*sitemap.*\.(xml|xsl)") {
    set $skip_cache 1;
}

# Don't use the cache for logged in users or recent commenters
if ($http_cookie ~* "comment_author|wordpress_[a-f0-9]+|wp-postpass|wordpress_no_cache|wordpress_logged_in") {
    set $skip_cache 1;
}

  location ~ \.php$ {
    fastcgi_pass unix:/run/php/php8.1-fpm.sock;
    fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
    include fastcgi_params;
    include snippets/fastcgi-php.conf;

fastcgi_cache phpcache;
fastcgi_cache_valid 200 301 302 60m;
fastcgi_cache_use_stale error timeout updating invalid_header http_500 http_503;
fastcgi_cache_min_uses 1;
fastcgi_cache_lock on;
add_header X-FastCGI-Cache $upstream_cache_status;
  }



  location ~ /\.ht {
    deny all;
  }

        # pass PHP scripts to FastCGI server
        #
        #location ~ \.php$ {
        #       include snippets/fastcgi-php.conf;
        #
        #       # With php-fpm (or other unix sockets):
        #       fastcgi_pass unix:/run/php/php7.4-fpm.sock;
       #       # With php-cgi (or other tcp sockets):
        #       fastcgi_pass 127.0.0.1:9000;
        #}

        # deny access to .htaccess files, if Apache's document root
        # concurs with nginx's one
        #
        #location ~ /\.ht {
        #       deny all;
        #}









}
# set client body size to 8M #
client_max_body_size 8M;

example of the problem

1   http://ro.example.com/  301 Moved Permanently   
Visit
2   https://ro.example.com/ 301 Moved Permanently   
Visit
3   https://ro.example.com/ 301 Moved Permanently   
Visit
4   https://ro.example.com/ 301 Moved Permanently   
Visit
5   https://ro.example.com/ 301 Moved Permanently   
Visit
6   https://ro.example.com/ 301 Moved Permanently   
Visit
7   https://ro.example.com/ 301 Moved Permanently   
Visit
8   https://ro.example.com/ 301 Moved Permanently   
Visit
9   https://ro.example.com/ 301 Moved Permanently   
Visit
10  https://ro.example.com/ 301 Moved Permanently

way to many redirects same thing have for www version not just the subdomains

What i would to have a clear nginx configuration where everything redirects to https:///www for main domain and https://ro.example.com for subdomains with only 1 301 redirect not multiple redirects

p.s. I also use fastcgi cache and cloudflare

UPDATE: i manage to make it work using cloudflare strict SSL, but now the non www version don't work says error connecting to the database

example www version working example non www version not working

UPDATE 2

I manage to fix this to with a server reboot but why this happen big mistery.