place fixed-top elements above one another bootstr

I'm trying to let users get informed to enable javascript for better use of the website to I want the message placed above the navigation bar using bootstrap, but instead, they stack upon one another. Don't mind how I describe this.

I want them to be placed in this manner:

But they stack on top of each other this way:

Using Bootstrap 4, please any ideas?

Here's some section of the code

<html>
    ...
    <body>
        <noscript class='bg-danger text-light py-2 text-center d-block fixed-top mb-4' style='z-index: 9999;'>Enable javascript to use App better.</noscript>
        <header class='navbar fixed-top navbar-expand-lg navbar-light bg-light'>
            <div class='container'>
                ...
            </div>
        </header>
        ...
    </body>
</html>

In the code below the div parts:

<div class='bg-danger text-light py-2 text-center mb-0'>Enable javascript to enhance this App.</div>

would need to be replaced with noscript. The div is just for easy testing/visibility.

To make the whole thing work, you move everything into a div with the fixed-top class and then add your noscript line followed by the navbar code.

Then you'll also need to add something like style="margin-top: 120px;" to the main container that would follow the fixed-top div to push the main content down.

Click the "run code snippet" button below and expand to full page:

<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/css/bootstrap.min.css" integrity="sha384-Gn5384xqQ1aoWXA+058RXPxPg6fy4IWvTNh0E263XmFcJlSAwiGgFAW/dAiS6JXm" crossorigin="anonymous">

<script src="https://code.jquery.com/jquery-3.2.1.slim.min.js" integrity="sha384-KJ3o2DKtIkvYIK3UENzmM7KCkRr/rE9/Qpg6aAZGJwFDMVNA/GpGFF93hXpG5KkN" crossorigin="anonymous"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.12.9/umd/popper.min.js" integrity="sha384-ApNbgh9B+Y1QKtv3Rn7W3mgPxhU9K/ScQsAP7hUibX39j7fakFPskvXusvfa0b4Q" crossorigin="anonymous"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/js/bootstrap.min.js" integrity="sha384-JZR6Spejh4U02d8jOt6vLEHfe/JQGiRRSQQxSfFWpi1MquVdAyjUar5+76PVCmYl" crossorigin="anonymous"></script>

<div class="fixed-top">
    <div class='bg-danger text-light py-2 text-center mb-0'>Enable javascript to enhance this App.</div>
    <nav class="navbar navbar-expand-lg navbar-light bg-light">
        <div class="container">
            <a class="navbar-brand" href="#">Navbar</a>
            <button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarSupportedContent" aria-controls="navbarSupportedContent" aria-expanded="false" aria-label="Toggle navigation">
                <span class="navbar-toggler-icon"></span>
            </button>

            <div class="collapse navbar-collapse" id="navbarSupportedContent">
                <ul class="navbar-nav mr-auto">
                    <li class="nav-item active">
                        <a class="nav-link" href="#">Home <span class="sr-only">(current)</span></a>
                    </li>
                    <li class="nav-item">
                        <a class="nav-link" href="#">Link</a>
                    </li>
                    <li class="nav-item dropdown">
                        <a class="nav-link dropdown-toggle" href="#" id="navbarDropdown" role="button" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
                            Dropdown
                        </a>
                        <div class="dropdown-menu" aria-labelledby="navbarDropdown">
                            <a class="dropdown-item" href="#">Action</a>
                            <a class="dropdown-item" href="#">Another action</a>
                            <div class="dropdown-divider"></div>
                            <a class="dropdown-item" href="#">Something else here</a>
                        </div>
                    </li>
                    <li class="nav-item">
                        <a class="nav-link disabled" href="#">Disabled</a>
                    </li>
                </ul>
                <form class="form-inline my-2 my-lg-0">
                    <input class="form-control mr-sm-2" type="search" placeholder="Search" aria-label="Search">
                    <button class="btn btn-outline-success my-2 my-sm-0" type="submit">Search</button>
                </form>
            </div>
        </div>
    </nav>
</div>

<p style="margin-top: 120px;">first line of text</p>