Nginx 504 timeout with Node app using node-mysql

Question

I have Nginx setup as a reverse proxy to my node app but I am getting a 504 timeout whenever I try to connect.

Below is the express app

const express = require('express')
var mysql = require('mysql');
const app = express()
const port = 3000

const db = mysql.createConnection({
  host     : '147.135.85.163',
  user     : 'u34364_yMVj9u64s4',
  password : 'G75q9S9VG2PF3Kel',
  database : 's34364_teambans'
});

app.get('/api/get_guardbans', (req, res) => {

  db.query('SELECT * FROM tf2jr_guardbans_logs', (error, results, fields) => {
    if (error) throw error;
    res.send(JSON.stringify(results))
  });

})

app.listen(port, () => {
  console.log(`Listening at http://localhost:${port}`)
})

This is the nginx config I have

location /api {
                proxy_set_header X-Real-IP $remote_addr;
                proxy_set_header Host $http_host;
                proxy_http_version 1.1;
                proxy_set_header Connection "";
                proxy_pass http://localhost:3001/api;
        }

I tried setting the timeouts like this questions suggest, however that doesn't work