nginx reverse proxy configuration - 404 not found

Question

I have a react app running on nginx(443) and spring server application(8443). Both are SSL secured. In local everything is working well. The problem is after deploying to dev - thats why I'm pretty sure it;s nginx config issue. Here's my file :

server {
          listen 443 ssl;
   server_name 193.xxx.xx.xxx;

    ssl_certificate nginx.crt;
    ssl_certificate_key nginx.key;
    ssl_protocols TLSv1 TLSv1.1 TLSv1.2 TLSv1.3;
    ssl_ciphers HIGH:!aNULL:!eNULL:!EXPORT:!CAMELLIA:!DES:!MD5:!PSK:!RC4;
    ssl_prefer_server_ciphers on;


   root /var/www/193.xxx.xx.xx;
   index index.html;

    # Add access log
   access_log /var/log/nginx/access.log;

   # Add error log
   error_log /var/log/nginx/error.log;


      location / {
        proxy_pass  https://193.xxx.xx.xx:8443;
        proxy_ssl_verify off;
        proxy_set_header    Host $host;
        proxy_set_header    X-Real-IP   $remote_addr;
        proxy_set_header    X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_connect_timeout 1;
        proxy_next_upstream error timeout http_500 http_502 http_503 http_504 http_404;
        proxy_intercept_errors on;

        allow all;
     error_page  405     =200 $uri;

        try_files $uri $uri/ /index.html;
    }

        location ~ /.well-known {
                allow all;
}
}

If I remove proxy block everything works well of course except api calls. What am I doing wrong ? I'm stuck.

This is what I receive :