Why would faker produce duplicate data?

I'm using Faker in order to seed a database, I'm doing this using faker methods and lodash#random.

Data generation is inside a loop, but on every execution is producing whole duplicates, how can I avoid it?

faker.locale = "es";
var leagueTeams = [{ "name" : "Perú","id" : "t834"},{"name" : "Venezuela","id" : "t833"},{"name" : "Argentina","id" : "t632"},{"name" : "Uruguay","id" : "t837"},{"name" : "Colombia","id" : "t832"},{"name" : "Bolivia","id" : "t836"},{"name" : "Jamaica","id" : "t1723"},{"name" : "Brazil","id" : "t614"},{"name" : "Mexico","id" : "t659"},{"name" : "Ecuador","id" : "t830"},{"name" : "Chile","id" : "t831"},{"name" : "Paraguay","id" : "t835"}]


for (var i = 0; i < 10; i++) {

    var fakeName = faker.name.findName();
    var fakeEmail = faker.internet.email();
    var fakePassword = faker.internet.password();
    var fakeTeam = faker.hacker.phrase();
    var fakeTeamImage = faker.image.imageUrl();
    var fakeFavoriteTeam  = leagueTeams[_.random(0,11)];
    var fakeBirthday = faker.date.past();

    // Create account
    request.post(  {url:'http://localhost:1337/api/v1/auths/login',
                    form:   {
                                email: fakeEmail,
                                password: fakePassword,
                            }
                    },
                    function (err, httpResponse, body) {

                            body = JSON.parse(body);
                            var iduser = body.user.id;
                            var auth = "Bearer " + body.token;

                            // Create team

                            request.put({
                                            url: 'http://localhost:1337/api/v1/users/' + iduser,
                                            form: {
                                                    name: fakeName,
                                                    gender: ['male','female'][i%2],
                                                    team: {name: fakeTeam, image: fakeTeamImage},
                                                    fanOf: {
                                                        name: fakeFavoriteTeam.name,
                                                        id: fakeFavoriteTeam.id
                                                    },
                                                    birthDate: fakeBirthday,
                                                    iduser: iduser
                                            },
                                            headers: {"Authorization": auth}
                                        },
                                        function (err, httpResponse, body) {
                                            console.log(body);
                                        }
                            );
                    });
}

So whole faker methods like faker.internet.findName(), faker.hacker.phrase() or the statement using lodash var fakeFavoriteTeam = leagueTeams[_.random(0,11)]; is always producing the same result, how could I improve it?