I dont know what im going wrong in this code ?

var Profile = require("./profile.js");


//2 handle the http route GET / and POST / i.e Home
let home = (request, response) => {

    //if url === '/' && 'GET'
    if (request.url === '/') {
        response.writeHead(200, { 'Content-Type': 'text/plan' });
        response.write("Header\n");
        response.write("Search\n");
        response.end("footer\n");
    }
    //show search

    //if url ==='/' && 'POST'
    //redirect to /:username
}

//3 handle http route GET /username i.e /chalker
let user = (request, response) => {

    //if url ==='/...'
    var username = request.url.replace("/", "");
    if (username.length > 0) {
        response.writeHead(200, { 'Content-Type': 'text/plan' });
        response.write("Header\n");

        //get json from treehouse
        var studentProfile = new Profile("username");
        //on "end"
        studentProfile.on("end", (profileJSON) => {

            //store the value which we need
            let values = {
                avatarUrl: profileJSON.gravatar_url,
                username: profileJSON["profile_name"],
                badges: profileJSON.badges.length,
                javascriptPoint: profileJSON.points["JavaScript"]
            };
            //simple response
            console.log(values.javascriptPoint);
            response.write(values.username + " has "+ values.badges + " badges " + "\n");
            response.end("footer\n");
        });
        studentProfile.on("error", (error) => {
            response.end("footer\n");
        });




        //show profile
        //on "error"
        //show error
    }

}
module.exports.home = home;
module.exports.user = user;