Add Jquery code does not work

Hey Freek,
I see you have the error: Uncaught TypeError: $ is not a function
your top half of the code is javascript, but the second half is jQuery which needs to be wrapped with this:

(function($) {
//your code here
})(jQuery);

like this:

<style>
.bootstrap .player-selection-ul li.player-selection-li{
padding: 6px 15px;
line-height: 1;
}
</style>
<link href="https://nl.escapeall.com/Content/API/styles.css" rel="stylesheet">
<link href="https://nl.escapeall.com/CustomCss/fun-thrills.css" rel="stylesheet">
<script type="text/javascript">
function updatePlayersOptions(element) {
    var jThis = ea_jQuery(element);
    const selectedLanes = parseInt(jThis.find('option:selected').data('quantity')) || 0;
    const maxPlayers = selectedLanes * 6;
    jThis.closest(".alert-reservation-added").find('.extra-options-row-2 option').each(function () {
        const playerCount = parseInt(ea_jQuery(this).val()) || 0;
        if (playerCount > maxPlayers) {
            ea_jQuery(this).prop('disabled', true).hide();
        } else {
            ea_jQuery(this).prop('disabled', false).show();
        }
    });
}
(function($) {
$(document).ready(function() {
$.getScript("https://nl.escapeall.com/Scripts/API/all.js", function (data, textStatus, jqxhr) {
GetBookingCalendra('#BookingId', {
        ServiceId: ['23fa314b-449e-4881-9b8d-3674fa6bdeab'],
        lang: 'nl',
        Template: 9,
        QuantitySelectionAsPlayers: true,
        FirstWeekDay: 'Monday',
        InitialQuantity: 1,
        successReservationSelected: function (reserv) {
            console.log('hello');
        },
        success: function () {
            ea_jQuery('.choose-player-panel h4').text('Aantal banen');
            ea_jQuery('.service-time-selection-panel h4').text('Tijd en Prijs');
            ea_jQuery('.player-selection-ul li[data-quantity="1"]').html('1<br/><small>1-6 spelers</small>');
            ea_jQuery('.player-selection-ul li[data-quantity="2"]').html('2<br/><small>2-12 spelers</small>');
            ea_jQuery('.player-selection-ul li[data-quantity="3"]').html('3<br/><small>3-18 spelers</small>');
            ea_jQuery('.player-selection-ul li[data-quantity="4"]').html('4<br/><small>4-24 spelers</small>');
            ea_jQuery('.service-time-selection-panel h4').text(' Activiteit en tijd');
            ea_jQuery(document).on('change', '.multiple-reservation-price', function (e) {
                updatePlayersOptions(this);
            });
        },
        successReservationSelected: function (toBeAppended) {
            updatePlayersOptions(ea_jQuery(".multiple-reservation-price", toBeAppended));
        }
    });
});
});
})(jQuery);
</script>
<div id="BookingId"></div>
<div class="escapeall">Booking System powered by: <a href="https://nl.escapeall.com/">Escape<span>All</span></a></div>

Best regards,
Mike