How do I remove a prefix from an NGINX proxy_pass (rewrite doesn't seem to work)?

Question

I have the following...

version: '2'
services:
  main-nginx:
    image: nginx:latest
    container_name: nginx
    volumes:
      - ./nginx/nginx.conf:/etc/nginx/conf.d/default.conf
      - ./nginx/src:/usr/src
    ports:
      - "80:80"
      - "443:443"
  ui:
    container_name: ui
    image: cbusha-ui:latest
  be:
    container_name: be
    image: cbusha-be:latest
    ports:
      - "8080:8080"
server {
    listen 80;
    listen  443 ssl;
    ssl_certificate /usr/src/site.crt;
    ssl_certificate_key /usr/src/site.key;
    server_name me.com;
    # include /usr/src/allow-cloudflare-only.conf
    location /services {
        rewrite /services/(.*) /$1  break;
        proxy_pass  http://be:8080;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection "upgrade";
        proxy_set_header HOST $host/work;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header X-Frame-Options SAMEORIGIN;
    }
    location / {
        proxy_pass  http://ui:3000/;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection "upgrade";
        proxy_set_header Host $http_host;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header X-Frame-Options SAMEORIGIN;
    }
}

When I try to access the backend directly it works fine...

But when I try to use the NGINX proxy I get a 400

What am I missing?

Note the ui works fine so...

Also to be clear the names in the urls such as http://be:8080 is the container name in docker so those have been forwarded to localhost to prove it works but I can also run it directly on the container as is...

Update

So I changed it to

location /services {
  proxy_pass  http://be:8080/;
  proxy_set_header Upgrade $http_upgrade;
  proxy_set_header Connection "upgrade";
  proxy_set_header HOST $host;
  proxy_set_header X-Real-IP $remote_addr;
  proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
}

But I still get a 400 when I call

https://localhost/services/heartbeat

and a 200 when I call

http://localhost:8080/heartbeat