Facebook page does not open with click - nightwatch

Hello, I recently started working with Nightwatch.js . I want to test the click on the facebook icon.

The code is this:

module.exports = {
        "Facebook link" : function (browser) {
            browser
                .url(http://m.unitel.ao/fit/)
                .waitForElementVisible('.socal', 3000)
                .waitForElementPresent('.fa.fa-facebook', 15000)
                .useCss().click('.fa.fa-facebook')
                .pause(3000)
                .assert.urlContains('facebook')
                .end()}};

Result is this:

> Running:  Facebook link
         ? Element <.socal> was visible after 118 milliseconds. 
         ? Element <.fa.fa-facebook> was present after 21 milliseconds. 
         ? Testing if the URL contains "facebook".  - expected "facebook" but got: http: //m.unitel.ao/fit/

While running the test it does not open the facebook page. Can someone help and tell you what is wrong?