unable to end the mysql connection using the mysql2 promise

Followings are my piece of code, please have a look into it.

var mysql = require('promise-mysql');
            var connection;

            mysql.createConnection({host:'Ip', user:'qa', password: '******'}).then(function(conn){
                connection = conn;
                return connection.query(firstInput);
            })
                .then(function(rows){
 console.log(rows);
})
                .then(function(){
                console.log("End of DB Con.");
                return connection.end();
                
            })
                .catch(function(error){
                //logs out the error
                console.log(error);
            });

The issue only provides a JavaScript promise-mysql connection chain; no repository file, test, or entry point is named. Start by reproducing the connection and end sequence from the example, then inspect the mysql2 promise connection API and existing connection-close tests if present. Done means the reported inability to end the connection is reproduced, explained, and covered by a passing regression test.