Nginx Confiuration for reverse proxy with multiple tomcat instances

I am first time working with Nginx.

• I have two servers. SERVER ONE (ip : 1.2.3.4) SERVER TWO (ip : 5.6.7.8)
• I have Installed nginx on SERVER ONE and Tomcat on SERVER TWO.

• I have successfully configured tomcat to run on different port. My tomcat is running on following ports.

  5.6.7.8:8080
  5.6.7.8:8081
  5.6.7.8:8082
  

• I have also deployed my war file on tomcat(each of the instance).

• I have configured my nginx as follows

• created a default.conf in /etc/nginx/conf.d

• Made changes to the file according the following link Nginx Configuration

  server {
          listen 80 default_server;
          listen [::]:80 default_server ipv6only=on;
      # Make site accessible from http://localhost/
      server_name 1.2.3.4;
  
      location / {
              proxy_pass http://www.example.com;
              # First attempt to serve request as file, then
              # as directory, then fall back to displaying a 404.
              try_files $uri $uri/ =404;
              # Uncomment to enable naxsi on this location
              # include /etc/nginx/naxsi.rule
      }
  
      location /user/{
              proxy_pass http://5.6.7.8:8080$uri;
  
              # First attempt to serve request as file, then
              # as directory, then fall back to displaying a 404.
              try_files $uri $uri/ =404;
              # Uncomment to enable naxsi on this location
              # include /etc/nginx/naxsi.rule
      }
  

  }

• The name of War file which I deployed on SERVER TWO is Example.
  which contains a api /user/login?param1=xyz&param2=abc&param3=mno

• When I hit the ip 1.2.3.4, it goes to root(/). I am getting the expected result.I am getting the example.com page.
• But when I hit 1.2.3.4/user, I am getting 404 not found. I was expecting that my api will be called and I will get the result.
• To check whether my api is working or not if I hit
  5.6.7.8:8080/Example//user/login?param1=xyz&param2=abc&param3=mno. I am getting the correct json result which I was expecting.
• And this same result I am expecting when I hit 1.2.3.4/user.But I am getting 404.

What all things I have to change in order to get the result when I hit 1.2.3.4/user

Thank you