Twitter Bootstrap nav collapse Hide on click

When I click on a menu item , the menu does not close , already checked the imports of JS and CSS and seemingly everything OK , there is something else I need to do to run the menu?

<!-- Fixed navbar -->
<nav class="navbar  navbar-default  navbar-fixed-top">
    <div class="container-fluid">
        <div class="navbar-header">
            <button type="button" class="navbar-toggle" data-toggle="collapse" data-target=".navbar-collapse">
    <span class="icon-bar"></span>
    <span class="icon-bar"></span>
    <span class="icon-bar"></span>
  </button>

        </div>
        <div class="collapse navbar-collapse" id="myNavbar">
            <ul class="nav navbar-nav">
                <li class="active"><a href="#home" class="active scroll">Home</a></li>
                <li><a href="#about" class="scroll">Sobre</a></li>
                <li><a href="#services" class="scroll">Serviços</a></li>
                <li><a href="#testimonials" class="scroll">Opiniões</a></li>
                <li><a href="#gallery" class="scroll">Gallery</a></li>
                <li><a href="#news" class="scroll">News</a></li>
                <li><a href="#contact" class="scroll">Contact</a></li>
            </ul>
        </div>
    </div>
</nav>