MySQL query data returns null GraphQL node.js

I’m having trouble handling MySQL query data in the resolve function of GraphQL objects. The data returns null in GraphiQL despite printing with console.log(). I’ve tried using JSON.parse().

I have the following code:

Schema.js

const graphql = require('graphql');
const queries = require('../mysql/queries');

const {
    GraphQLObjectType,
    GraphQLString,
    GraphQLSchema,
    GraphQLID,
    GraphQLInt,
    GraphQLFloat,
    GraphQLList,
    GraphQLNonNull
} = graphql;

const AccountType = new GraphQLObjectType({
    name: 'Account',
    fields: () => ({
        id: { type: GraphQLID },
        email: { type: GraphQLString },
        phone: { type: GraphQLString },
        password: { type: GraphQLString }
    })
});

const RootQuery = new GraphQLObjectType({
    name: 'RootQueryType',
    fields: {
        account: {
            type: AccountType,
            args: { 
                email: { type: GraphQLString },
                password: { type: GraphQLString }
            },
            async resolve(parent, args) {
                return await queries.login(args.email, args.password);
            }
        }


module.exports = new GraphQLSchema({
    query: RootQuery
})

queries.js

var connection = require('./connection');
var db = connection.connect();

module.exports = {
    login: (email, password) => {
        return new Promise((resolve) => {
            var account = `SELECT id FROM accounts WHERE email="${email}" AND password="${password}"`;
            db.query(account, (err, result) => {
                if (err) throw err;
                if (isEmpty(result[0])) return resolve(null);
                else return resolve(result);
            })
        })
    }
}