App.layout Crashing the Ajax function used in View

App.blade

<!-- CSRF Token -->
<meta name="csrf-token" content="{{ csrf_token() }}">

<title>{{ config('app.name', 'Healthfix Pharma') }}</title>

<!-- Styles -->
<link href="{{ asset('css/app.css') }}" rel="stylesheet">
<script>
    window.Laravel = {!! json_encode([
        'csrfToken' => csrf_token(),
    ]) !!};
</script>

                <!-- Collapsed Hamburger -->
                <button type="button" class="navbar-toggle collapsed" data-toggle="collapse" data-target="#app-navbar-collapse">
                    <span class="sr-only">Toggle Navigation</span>
                    <span class="icon-bar"></span>
                    <span class="icon-bar"></span>
                    <span class="icon-bar"></span>
                </button>

                <!-- Branding Image -->
                <a class="navbar-brand" href="{{ url('/') }}">
                    {{ config('app.name', 'Healthfix Pharma') }}
                </a>
            </div>

            <div class="collapse navbar-collapse" id="app-navbar-collapse">
                <!-- Left Side Of Navbar -->
                <ul class="nav navbar-nav">
                    &nbsp;
                </ul>

                <!-- Right Side Of Navbar -->
                <ul class="nav navbar-nav navbar-right">
                    <!-- Authentication Links -->
                    @if (Auth::guest())
                        <li><a href="{{ route('login') }}">Login</a></li>
                        <!--li><a href="{{ route('register') }}">Register</a></li-->
                    @else
                        <li class="dropdown">
                            <a href="#" class="dropdown-toggle" data-toggle="dropdown" role="button" aria-expanded="false">
                                {{ Auth::user()->username }} <span class="caret"></span>
                            </a>

                            <ul class="dropdown-menu" role="menu">
                                <li>
                                    <a href="{{ route('logout') }}"
                                        onclick="event.preventDefault();
                                                 document.getElementById('logout-form').submit();">
                                        Logout
                                    </a>

                                    <form id="logout-form" action="{{ route('logout') }}" method="POST" style="display: none;">
                                        {{ csrf_field() }}
                                    </form>
                                </li>
                            </ul>
                        </li>
                    @endif
                </ul>
            </div>
        </div>
    </nav>

    @yield('content')
</div>

<!-- Scripts -->

<script src="{{ asset('js/app.js') }}"></script>

And here is my page added only the code

@extends('layouts.app') @section('content')

<meta name="_token" content="{!! csrf_token() !!}"></meta>
<meta name="viewport" content="width=device-width, initial-scale=1">
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css">
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<script type="text/javascript">
jQuery.noConflict();
</script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.min.js"></script>

Enter Sampling $.ajaxSetup({ headers: { 'X-CSRF-TOKEN': $('meta[name="_token"]').attr('content') } })

//----------------- Clicking on Add Customer ------
jQuery('#add').on('click',function(){
  alert("hi");
  $('#save').val('Save');
  $('#frmRepresentative').trigger('reset');

  $('#Retailer').modal('show');
});

@endsection