No response when using ManagementClient in AWS Lambda

Hi all,

We are building a serverless service to perform user management by using node-auth0 sdk but it cannot work as well as the direct api call.

//aws lambda
exports.handler = async (event) => {
    const auth0Management = await createAuth0Management();

    let response;
    const requestBody = JSON.parse(event.body.toString());
    const createUserResponse = await createAuth0User(auth0Management, requestBody);
    response = buildResponse(200, createUserResponse);
    return response;
};

async function createAuth0Management(){
    return new ManagementClient({
        domain: process.env.DOMAIN,
        clientId: process.env.CLIENTID,
        clientSecret: process.env.CLIENTSECRET,
        scope: process.env.SCOPE
     });
}

function buildResponse(statusCode, body){
    return {
        statusCode: statusCode,
        headers:{
            'Access-Control-Allow-Origin': '*',
            'Content-Type': 'application/json'
        },
        body: JSON.stringify(body)
    }
}

async function createAuth0User(auth0Management, userInfo){
    const body = {
        email: userInfo[0],
        username: userInfo[1],
        password: userInfo[2],
        connection: 'xxx'
    };
    //sdk cannot create user
    await auth0Client.createUser(body)
    		.then(function (response){
		        console.log(`create user success: ${response}`); // <- can not see in cloudwatch
		    })
        	.catch(function (err) {
		        console.log(`create user error: ${err}`); // <- can not see in cloudwatch
		    });
}

However, we can create the user by calling the api directly

async function createAuth0User(auth0Management, userInfo){
    const body = {
        email: userInfo[0],
        username: userInfo[1],
        password: userInfo[2],
        connection: 'xxx'
    };
    //api can create user
    await doPostRequest(body).then(()=> {
    	console.log('created');	// <- it works
    })
}

const doPostRequest = (body) => {
    return new Promise((resolve, reject) => {
        const options = {
            host: 'xxx',
            path: '/api/v2/users',
            method: 'POST',
            headers: {
                'Content-Type': 'application/json',
                'Authorization':"Bearer xxx"
            }
        };

        //create the request object with the callback with the result
        const req = https.request(options, (res) => {
            resolve(JSON.stringify(res.statusCode));
        });

        // handle the possible errors
        req.on('error', (e) => {
            reject(e.message);
        });

        //do the request
        req.write(JSON.stringify(body));

        //finish the request
        req.end();
    });
};

Could anyone some help on this, please? Thanks.